Torrential rains in Oklahoma; Summer in March continues for Midwest

By: Dr. Jeff Masters , 2:07 PM GMT on March 20, 2012

Share this Blog
27
+

A significant flood event is underway in Eastern Oklahoma, where widespread rainfall amounts of 3 to 5 inches have fallen since yesterday. Up to four more inches of rain is likely today, and the National Weather Service in Tulsa is warning of the potential for "widespread and potentially catastrophic areal flooding and river flooding" should some of the higher rainfall amounts being forecast materialize. Numerous main-stem rivers across eastern Oklahoma and northwest Arkansas are now approaching flood stage, and will likely experience moderate to major flooding into Wednesday. Rainfall has also been heavy over Eastern Texas, with widespread amounts of 2 - 4 inches. These heavy rains are causing some street flooding, but in general, will be a benefit, as moderate to severe drought conditions still cover most of the region.


Figure 1. Radar-estimated rainfall for Eastern Oklahoma since March 19, 2012, as estimated by the Tulsa, Oklahoma radar.

The storm system responsible is a massive, slow-moving trough of low pressure over the Western U.S. that is colliding with the warmest and moistest air mass ever recorded in March in the Central and Eastern U.S. According to the NWS in Minneapolis, Minnesota, moisture flowing northwards into Minnesota along the cold front early this week had the highest levels of moisture ever recorded so early in the year. At the boundary between the Western U.S. trough of low pressure and Central U.S. ridge of high pressure, a cold front is lifting huge quantities of moisture-laden air aloft, forcing torrential rains to fall. The cold front is also expected to trigger a Slight Risk of severe weather over East Texas, Western Louisiana, and Southern Arkansas today, says NOAA's Storm Prediction Center. Severe thunderstorm watches are already posted for much of East Texas, as seen on our Severe Weather Map. Three tornadoes were reported yesterday in Texas, and eleven touched down the previous day in Oklahoma, Nebraska, and South Dakota. The tornado that hit North Platte, Nebraska two days ago was rated a strong EF-3, and injured four people.


Figure 2. Predicted rainfall amounts for the 2-day period Tuesday morning through Thursday morning show an area of 3+ inches (orange colors) is expected over Eastern Oklahoma, Arkansas, Louisiana, and Southwest Missouri. Image credit: NOAA HPC.

Summer in March continues for the Midwest
The ongoing March heat wave in the Midwest will continue to set all-time heat records through Thursday, gradually shifting its peak intensity eastwards during the week. A few highlights from yesterday's records:

Pellston, Michigan in the Northern Lower Peninsula is called "Michigan's Icebox", since it frequently records the coldest temperatures in the state, and in the entire nation. But the past three days, Pellston has topped out at 80° - 82°F, the first 80°F March days in their history. Yesterday's 82° reading broke the previous record for the date (56° in 1976) by an amazing 26°, and was 44°F above average. Nearby Traverse City hit 83°F yesterday, the third consecutive day the city has experienced its hottest March temperature on record.

International Falls, Minnesota hit 78°F yesterday, 42° above average, and the 2nd hottest March temperature on record in the Nation's Icebox. The record of 79°F was set the previous day. Remarkably, the low temperature for International Falls bottomed out at 60°F yesterday, tying the previous record high for the date. I've never seen a station with a century-long data record have its low temperature for the date match the previous record high for the date. Yesterday was the seventh consecutive day that International Falls broke or tied a daily record. That is spectacularly hard to do for a station with a century-long weather record. The longest string of consecutive records being broken I'm aware of is nine days in a row, set June 2 - 10, 1911 in Tulsa, Oklahoma (with weather records going back to 1905.) International Falls has a good chance of surpassing nine consecutive records this week.

Record heat in Canada
Record-breaking heat has also penetrated into the Prairie provinces of Canada over the past week. Winnipeg, Manitoba has broken its record high for the past five days in a row, and hit 24°C (75.2°F) yesterday, its hottest March temperature on record. Forecast high temperatures for Wednesday and Thursday across Ontario are near 26°C, which will threaten the records for hottest March day in history for Windsor, London, Hamilton, and Toronto.


Figure 3. The jet stream pattern features a large, southwards dipping bulge over the Western U.S., creating a trough of low pressure with cold and snow, and a large, northwards looping bulge over the Central U.S., creating a record-strength ridge of high pressure.

Why the record early-season warmth?
The unusual warmth is due to a loop in the jet stream that has created a large upper-level ridge of high pressure that is stuck in place over the Eastern U.S.--a phenomenon known as a "blocking pattern." Since the jet stream acts as the boundary between cold air to the north and warm air to the south, and the large loop in the jet places its axis far to the north of the eastern U.S., summer-like warmth has developed over the eastern half of the U.S. Conversely, colder than average temperatures have developed over the western third of the U.S. behind the southwards-dipping loop of the jet stream. This jet stream pattern is too extreme to be stable, and the big loop over the Western U.S. will break off and form a giant eddy on Wednesday. The resulting area of low pressure will be known as a "cut-off low", because it will be cut off from the jet stream. The cut-off low will drift slowly eastwards during the week, gradually bringing an end to "Summer in March" over the Eastern half of the U.S.

Jeff Masters

Lake Fog After T-storm (spacey84)
Lake Fog After T-storm
()
Spring Suprise (Lou427)
First and last snow of winter !
Spring Suprise

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 186 - 136

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11Blog Index

Quoting CycloneUK:



I have no quarrel with the science that the earths axis shifts after Earthquakes, but claiming that the earths axis shift actually causes the Earthquakes and making predictions about when the next one will strike with no basis, is sensastionalist nonsense.
Member Since: Posts: Comments:
Quoting ycd0108:
# 162:
"I ain't superstitious
But a Black Cat just crossed my path."
Seems that a lot of fairly intelligent people (and a few boneheads like myself) are taking an interest.
As the building inspector who failed my footings the other day said when I told him the footings were at least 6" into "Hard Pan" and invited him to get down in any footing hole and chip some out:
"You don't know and I don't know so I require a "geotech" report.
250$ later the report said: "Hard Pan"


I'm a Geotech
Member Since: Posts: Comments:
Quoting BobWallace:
New paper published that may help pull together a lot of what we are experiencing.



Weather isn't some sort of random events strung together, it isn't "Mother Nature showing us who's boss", it's physics.


It maybe Physics, but we tend to believe that we are superior to mother nature
Member Since: November 6, 2010 Posts: 11 Comments: 8000
Quoting Jedkins01:
are you referring to the Earth's axis being shifted from a very severe earth quake as superstitious nonsense? Because if you are, you are incorrect, that is actually sound science as crazy as it sounds. Granted its a very small shift, but still crazy none the less.


I have no quarrel with the science that the earths axis shifts after Earthquakes, but it is claiming that the earths axis shift actually causes the Earthquakes and making predictions about when the next one will strike, with no basis, is sensastionalist nonsense.
Member Since: Posts: Comments:
Quoting Patrap:


This is EXACTLY what I was talking about!
Member Since: September 3, 2011 Posts: 13 Comments: 3471
# 162:
"I ain't superstitious
But a Black Cat just crossed my path."
Seems that a lot of fairly intelligent people (and a few boneheads like myself) are taking an interest.
As the building inspector who failed my footings the other day said when I told him the footings were at least 6" into "Hard Pan" and invited him to get down in any footing hole and chip some out:
"You don't know and I don't know so I require a "geotech" report.
250$ later the report said: "Hard Pan"
Member Since: Posts: Comments:
Quoting Patrap:



Quite a bit of rain in the Texas/Louisiana border
Member Since: November 6, 2010 Posts: 11 Comments: 8000
Knoxville is now at 85, believe it or not.

Yep, I think our official high will be 85. The airport is now reporting thunderstorm conditions, so that will effectively end anymore daytime heating. 85 beats the old record of 83.

My PWS is at 83.5 and has topped out at 84.0 so far today.
Member Since: Posts: Comments:
SEVERE THUNDERSTORM WARNING
NCC069-127-202130-
/O.NEW.KRAH.SV.W.0018.120320T2051Z-120320T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE RALEIGH NC
451 PM EDT TUE MAR 20 2012

THE NATIONAL WEATHER SERVICE IN RALEIGH HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
FRANKLIN COUNTY IN CENTRAL NORTH CAROLINA
WESTERN NASH COUNTY IN CENTRAL NORTH CAROLINA

* UNTIL 530 PM EDT

* AT 449 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 6 MILES NORTHEAST OF LOUISBURG...MOVING SOUTHWEST AT 10 MPH. QUARTER SIZED HAIL IS LIKELY WITH THIS STORM.

* LOCATIONS IMPACTED INCLUDE...
LOUISBURG...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A VEHICLE OR A NEARBY BUILDING. AS A LAST RESORT...LIE DOWN IN A LOW LYING AREA AND COVER YOUR HEAD WITH YOUR HANDS.

PLEASE REPORT SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE BY CALLING...1...8 7 7...6 3 3...6 7 7 2 OR NOTIFY YOUR LOCAL LAW ENFORCEMENT AGENCY.

&&

LAT...LON 3577 7812 3598 7842 3619 7825 3611 7800
TIME...MOT...LOC 2051Z 033DEG 11KT 3613 7820

$$

GIH
Member Since: August 4, 2011 Posts: 46 Comments: 4485
Im watching er,,

Have to pick up a friend flying down from Boston to MSY @ 10 CDT.

Member Since: July 3, 2005 Posts: 423 Comments: 128240
Quoting CycloneUK:


I can't believe you advocate that superstitious nonsense. Get a grip
are you referring to the Earth's axis being shifted from a very severe earth quake as superstitious nonsense? Because if you are, you are incorrect, that is actually sound science as crazy as it sounds. Granted its a very small shift, but still crazy none the less.
Member Since: August 21, 2008 Posts: 0 Comments: 7438
Quoting Patrap:




That's slowly heading your way Pat.

Member Since: Posts: Comments:


Magnitude 6.2 - PAPUA, INDONESIA
2012 March 20 17:56:19 UTC




Magnitude
6.2
Date-Time
Tuesday, March 20, 2012 at 17:56:19 UTC
Wednesday, March 21, 2012 at 02:56:19 AM at epicenter
Time of Earthquake in other Time Zones
Location
3.830°S, 140.220°E
Depth
66.9 km (41.6 miles)
Region
PAPUA, INDONESIA
Distances
153 km (95 miles) SSW of Jayapura, Papua, Indonesia
173 km (107 miles) SW of Vanimo, New Guinea, PNG
1407 km (874 miles) NE of DARWIN, Northern Territory, Australia
3711 km (2305 miles) E of JAKARTA, Java, Indonesia
Location Uncertainty
horizontal +/- 14 km (8.7 miles); depth +/- 8.8 km (5.5 miles)
Parameters
NST=180, Nph=180, Dmin=818.2 km, Rmss=0.92 sec, Gp= 22°,
M-type=body wave magnitude (Mb), Version=6
Source
Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)
Event ID
usc0008m6b
Member Since: July 3, 2005 Posts: 423 Comments: 128240
Quoting Jedkins01:


No I said from the start it tends to underestimate in a more tropical environment. If you misunderstood me maybe I made a couple typos but that's what I meant.


Got ya, I see now you were talking about Waco then Tampa
Member Since: Posts: Comments:
New paper published that may help pull together a lot of what we are experiencing.


Key Points:

Enhanced Arctic warming reduces poleward temperature gradient

Weaker gradient affects waves in upper-level flow in two observable ways

Both effects slow weather patterns, favoring extreme weather

Abstract:

Arctic amplification (AA) – the observed enhanced warming in high northern latitudes relative to the northern hemisphere – is evident in lower-tropospheric temperatures and in 1000-to-500 hPa thicknesses.

Daily fields of 500 hPa heights from the National Centers for Environmental Prediction Reanalysis are analyzed over N. America and the N. Atlantic to assess changes in north-south (Rossby) wave characteristics associated with AA and the relaxation of poleward thickness gradients.

Two effects are identified that each contribute to a slower eastward progression of Rossby waves in the upper-level flow: 1) weakened zonal winds, and 2) increased wave amplitude. These effects are particularly evident in autumn and winter consistent with sea-ice loss, but are also apparent in summer, possibly related to earlier snow melt on high-latitude land.

Slower progression of upper-level waves would cause associated weather patterns in mid-latitudes to be more persistent, which may lead to an increased probability of extreme weather events that result from prolonged conditions, such as drought, flooding, cold spells, and heat waves.

http://www.agu.org/pubs/crossref/2012/2012GL05100 0.shtml




Weather isn't some sort of random events strung together, it isn't "Mother Nature showing us who's boss", it's physics.

Member Since: Posts: Comments:
Member Since: Posts: Comments:


Member Since: July 3, 2005 Posts: 423 Comments: 128240
Quoting nigel20:

Maybe they should employ tou


Maybe. i would love to see the NWS in Raleigh, like tak a tour thru it.
Member Since: August 4, 2011 Posts: 46 Comments: 4485
upper level system winding up now
south of texas panhandle
comma head precip shield fills in
from se semi circle to the ne , nw , w
sw area should remain dry
snow should be from nw sector
to just before sw sector
as system meanders ene overtime
Member Since: Posts: Comments:
Orleans Parish

Coastal Flood Statement, Flash Flood Watch, Wind Advisory
Member Since: July 3, 2005 Posts: 423 Comments: 128240
Quoting StormTracker2K:


No, he said over represents rainfall totals for up north as the colume of air has more ice in it than lets say a more tropical enviroment. A tropical enviroment has a warmer colume of air.



Sometimes up north they are underestimated too like when a very tropically oriented system cuts up the Northeast like remnants from a tropical cyclone.


Often times the NWS will switch over to tropical Z/R relationship to help correct the underestimation issue, but they only due it during hurricanes or when its exceptionally a tropical environment. With the change to dual pole I'm quite sure the radar will preform quite a bit better with rainfall rates in a tropical environment. Although if I am correct even though many radars are upgraded we the general public won't get to actually see the improved radar changed till 2013 once all radars have upgraded. We still see older radar based images till then.
Member Since: August 21, 2008 Posts: 0 Comments: 7438
I have a new poll in my blog,this one about which names will be the big ones in the 2012 North Atlantic Hurricane season. If anyone wants to participate,visit my blog.

Link
Member Since: Posts: Comments:
Quoting SPLbeater:


And right after i say that, the NWS responds with a Severe Thunderstorm Warning.

:D that is 120 seconds on my score!

Maybe they should employ tou
Member Since: November 6, 2010 Posts: 11 Comments: 8000
Who here thinks that Low Pressure in the panhandle of Texas is going to produce more rain for SE Texas?
Member Since: Posts: Comments:
Quoting Patrap:


I can't believe you advocate that superstitious nonsense. Get a grip
Member Since: Posts: Comments:
Quoting jitterboy:


I'm confused Jed You said earlier that radar over represents rainfall in the tropics correct? But this post seems to give reasons why it would under represent rainfall.


No I said from the start it tends to underestimate in a more tropical environment. If you misunderstood me maybe I made a couple typos but that's what I meant.
Member Since: August 21, 2008 Posts: 0 Comments: 7438
Quoting jitterboy:


I'm confused Jed You said earlier that radar over represents rainfall in the tropics correct? But this post seems to give reasons why it would under represent rainfall.


No, he said over represents rainfall totals for up north as the colume of air has more ice in it than lets say a more tropical enviroment. A tropical enviroment has a warmer colume of air.
Member Since: Posts: Comments:
Quoting Tropicsweatherpr:
The CSU team of Klotzbach/Gray will release a brief update for the 2012 season on Wednesday.The more complete forecast will be released on April 4th. Read the press release below.


Phil Klotzbach and Bill Gray will put out a brief update for their outlook for the 2012 Atlantic basin hurricane season on Wednesday, March 21. This brief outlook will be released prior to the start of the National Hurricane Conference and will discuss some of the changes that have occurred in various large-scale atmosphere and ocean patterns since their initial outlook put out in early December. The probabilities for the four scenarios discussed in the early December outlook will be updated at that time. The first seasonal forecast with numbers will come out as originally scheduled on Wednesday, April 4.

Link

That should be interesting
Member Since: November 6, 2010 Posts: 11 Comments: 8000
This public information statement from the Chicago NWS office amused me.

000
NOUS43 KLOT 201301
PNSLOT

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
800 AM CDT TUE MAR 20 2012

SNOWFALL AND SNOW DEPTH REPORTS.

DATA PROVIDED BY NATIONAL WEATHER SERVICE CHICAGO AREA AND ROCKFORD
AREA SNOWFALL TEAM.

12 HR SNOWFALL 12 HR SNOWFALL TOTAL
LOCATION ENDING 6AM ENDING 6PM SNOW
TODAY YESTERDAY DEPTH AT 6AM
ILLINOIS

BEACH PARK 0.0 / 0.0 / 0
DOWNERS GROVE 0.0 / 0.0 / 0
LA GRANGE 0.0 / / 0
PEOTONE 0.0 / 0.0 / 0
PLAINFIELD 4SW 0.0 / / 0
WILLOWBROOK / 0.0 /
YORKVILLE 2SE / / 0

NORTHWEST INDIANA

SCHERERVILLE 0.0 / 0.0 / 0
Member Since: March 11, 2012 Posts: 0 Comments: 114
Quoting StormTracker2K:


Hey, to me a good rain at this point would be a 1/2 inch as it is getting very dry over in Orlando as well due to highs of 84 to 87 for over a week now when normal is 77.



I will take a half inch also, its better than the consistent 0.0 lately, lol. I'm just saying don't get too excited over a big event or anything because it should just be scattered convection, nothing too big. Although you never know, sometimes these little events can sneak up on you and do more than you would expect.

Anyways, yes its been very warm here also, it was in the mid 80's here for almost 2 weeks but lately its been 86 to 88 with strong easterly flow here. We actually hit 89 at my place today.


Member Since: August 21, 2008 Posts: 0 Comments: 7438


Magnitude 5.1 - OAXACA, MEXICO
2012 March 20 20:14:39 UTC


Magnitude
5.1
Date-Time
Tuesday, March 20, 2012 at 20:14:39 UTC
Tuesday, March 20, 2012 at 02:14:39 PM at epicenter
Location
16.529N, 98.007W
Depth
10.5 km (6.5 miles)
Region
OAXACA, MEXICO
Distances
23 km (14 miles) N (3) from Pinotepa Nacional, Oaxaca, Mexico
47 km (29 miles) ESE (111) from Ometepec, Guerrero, Mexico
89 km (56 miles) SSW (203) from Tlaxiaco, Oaxaca, Mexico
149 km (92 miles) WSW (247) from Oaxaca, Oaxaca, Mexico
207 km (128 miles) E (100) from Acapulco, Guerrero, Mexico
Location Uncertainty
horizontal /- 22.9 km (14.2 miles); depth /- 5 km (3.1 miles)
Parameters
NST=231, Nph=232, Dmin=528.8 km, Rmss=1.2 sec, Gp=158,
M-type=body wave magnitude (Mb), Version=9
Source
Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)
Event ID
usc0008m9e
Member Since: July 3, 2005 Posts: 423 Comments: 128240
Quoting StormTracker2K:


Great explanation Jed!


I'm confused Jed You said earlier that radar over represents rainfall in the tropics correct? But this post seems to give reasons why it would under represent rainfall.
Member Since: Posts: Comments:
Quoting SPLbeater:
Cell south of Lynchburg VA dont look too friendly..
VIL reflecting 45 kg/m^2, maybe possible hail


And right after i say that, the NWS responds with a Severe Thunderstorm Warning.

:D that is 120 seconds on my score!
Member Since: August 4, 2011 Posts: 46 Comments: 4485
Member Since: July 3, 2005 Posts: 423 Comments: 128240
The CSU team of Klotzbach/Gray will release a brief update for the 2012 season on Wednesday.The more complete forecast will be released on April 4th. Read the press release below.


Phil Klotzbach and Bill Gray will put out a brief update for their outlook for the 2012 Atlantic basin hurricane season on Wednesday, March 21. This brief outlook will be released prior to the start of the National Hurricane Conference and will discuss some of the changes that have occurred in various large-scale atmosphere and ocean patterns since their initial outlook put out in early December. The probabilities for the four scenarios discussed in the early December outlook will be updated at that time. The first seasonal forecast with numbers will come out as originally scheduled on Wednesday, April 4.

Link
Member Since: Posts: Comments:
Cell south of Lynchburg VA dont look too friendly..
VIL reflecting 45 kg/m^2, maybe possible hail
Member Since: August 4, 2011 Posts: 46 Comments: 4485
Quoting Jedkins01:



Actually that probably has a lot to do with it, but its also the processes in convection in a more tropical environment that's different. In general the column of air in Florida is going to be much warmer higher up in the cloud growth region than many areas further north. That being said radar beams tilt upward, and we know that ice shows a lot stronger reflectivity than liquid water.

Furthermore, in a more tropical environment, because of less ice, there ends up being a greater volume of water overall that is actually hitting the ground, so the radar misses some of this action.


Therefore, a a convective cloud in a column of relatively warm air will drop a lot greater volume of water then a cloud with more ice in it, even though the radar might think the cloud with more ice has heavier precip. That is partly why convection in tropical cyclones is often much heavier than the radar makes it appear, some more than others, depending on actual total water volume through the column and how warm the column is also.'


Of course warmth higher up isn't always a good thing, too much warm air further up can mean stable air and lack of convective development.


Great explanation Jed!
Member Since: Posts: Comments:
Quoting Jedkins01:



Actually that probably has a lot to do with it, but its also the processes in convection in a more tropical environment that's different. In general the column of air in Florida is going to be much warmer higher up in the cloud growth region than many areas further north. That being said radar beams tilt upward, and we know that ice shows a lot stronger reflectivity than liquid water.

Sooo radar would under represent in a tropical environment?



Furthermore, in a more tropical environment, because of less ice, there ends up being a greater volume of water overall that is actually hitting the ground, so the radar misses some of this action.

Soooo....again tropical radar will under represent rainfall totals I thought you said it over represents rainfall totals




Therefore, a a convective cloud in a column of relatively warm air will drop a lot greater volume of water then a cloud with more ice in it, even though the radar might think the cloud with more ice has heavier precip. That is partly why convection in tropical cyclones is often much heavier than the radar makes it appear, some more than others, depending on actual total water volume through the column and how warm the column is also.'


Of course warmth higher up isn't always a good thing, too much warm air further up can mean stable air and lack of convective development.
Member Since: Posts: Comments:
Quoting StormTracker2K:

These temps are what you would expect in the tropics at this time
Member Since: November 6, 2010 Posts: 11 Comments: 8000
Quoting drought:
Chicago NWS just raised the forecast for tomorrow from 80 to 82.

If that happens the first 21 days of March wouldn't tie for 7th warmest April. It would hold the 7th ranking solo.

Wow! That's all I can say
Member Since: November 6, 2010 Posts: 11 Comments: 8000
Quoting StormTracker2K:


I agree the radar est. seem to always be off the mark. In FL it seems as if the radar always under estimates the precip amounts. Maybe due to the deep tropical moisture that's always around us.



Actually that probably has a lot to do with it, but its also the processes in convection in a more tropical environment that's different. In general the column of air in Florida is going to be much warmer higher up in the cloud growth region than many areas further north. That being said radar beams tilt upward, and we know that ice shows a lot stronger reflectivity than liquid water. That is why we get less hail here generally speaking.

Furthermore, in a more tropical environment, because of less ice, there ends up being a greater volume of water overall that is actually hitting the ground, so the radar misses some of this action.


Therefore, a a convective cloud in a column of relatively warm air has the potential to drop a lot greater volume of water then a cloud with more ice in it, even though the radar might think the cloud with more ice has heavier precip. That is partly why convection in tropical cyclones is often much heavier than the radar makes it appear, some more than others, depending on actual total water volume through the column and how warm the column is also.'


Of course warmth higher up isn't always a good thing, too much warm air further up can mean stable air and lack of convective development.


However, don't misinterpret what I am saying. Let it be known that I'm not saying cold air aloft means you get less heavy rain. For example, the recent heavy rain even in Texas/Oklahoma had some impressive rain totals, but there were very steep lapse rates(cold air aloft). That's because moisture was very high. And after all, its relatively colder air aloft that can lead to a greater change for stronger convection and severe weather, which can also mean a heavier rain risk with stronger convection. Its just that a thunderstorm in a warmer column of air can dump potentially quite a bit more rain then one with colder air given that the moisture is also high, but if there isn't at least some decent cooling with height in comparison to the low levels then convection isn't strong enough and then rainfall is also less.



That being said, this might help you appreciate rainfall forecasting and that it can be quite hard, same thing with severe weather.
Member Since: August 21, 2008 Posts: 0 Comments: 7438
Quoting StormTracker2K:


Hey, to me a good rain at this point would be a 1/2 inch as it is getting very dry over in Orlando as well due to highs of 84 to 87 for over a week now when normal is 77.


How it was last spring in TX
Member Since: Posts: Comments:
What city is that forecast graphic for StormTracker2K?

Never mind, Orlando.
Member Since: March 11, 2012 Posts: 0 Comments: 114
Member Since: Posts: Comments:
Chicago NWS just raised the forecast for tomorrow from 80 to 82.

If that happens the first 21 days of March wouldn't tie for 7th warmest April. It would hold the 7th ranking solo.
Member Since: March 11, 2012 Posts: 0 Comments: 114
AWCN12 CWTO 202013
Updated weather summary for Northern Ontario issued by
Environment Canada at 4:07 PM EDT Tuesday 20 March 2012.

------------------------------------------------- ------------
==weather event discussion==
Today is the first day of spring. But it feels like the first day of
summer in parts of Northern Ontario. We are nearing the end of an
historic warm spell across Ontario with record temperatures tumbling
by the dozen every day. Almost 120 daily high temperature records
have been rewritten over the past week across the province. Some
records have been shattered by as much as 14 degrees.

Normally we are still feeling the chill of winter's final breath.
But instead, words such as humidex, daffodils and patio weather
Are on everybody's lips. Even across Northern Ontario the snow
Pack has been melting at inconceivable rates. For instance,
Geraldton reported 31 centimetres of snow on the ground on March
18th. Two days later it had virtually all melted.

It appears that this March will likely be the warmest March on
Record for some places.

This warm spell will last into Wednesday across Northeastern Ontario
before a cold front will introduce somewhat cooler air.

Below are record maximum temperature records set on Monday
19-mar-2012. Please refer to the table below for more details.

------------------------------------------------- ------------
Location new temperature record previous record

Kenora 23.8 11.3 (2000)
Red Lake 23.2 11.2 (2000)
Sioux Lookout 21.9 13.9 (1946)
Fort Frances 26.0 10.0 (2000)
Thunder Bay 17.4 12.2 (1946)
Upsala 22.9 9.8 (2003)
Geraldton 20.7 11.0 (1987)
Kapuskasing 25.1 11.7 (1970)
Timmins 23.6 12.2 (1970,1979)
Chapleau 23.9 9.5 (1980)
Wawa 20.0 10.3 (2003)
Sault Ste Marie 21.3 11.1 (1976)
Sudbury 20.3 8.3 (1970)
North Bay 22.8 11.7 (1946)

This weather summary contains preliminary information and may not
constitute an official or final report.

END/OSPC



------------------------------------------------- -------------------------------



AWCN11 CWTO 201859
Updated weather summary for all of Southern Ontario and the
National Capital Region issued by Environment Canada
At 1:32 PM EDT Tuesday 20 March 2012.

------------------------------------------------- ------------
==weather event discussion==

Today is the first day of spring. But it feels like the first day
Of summer. We are in the midst of an historic warm spell across
Ontario with record temperatures tumbling by the dozen every day.
Almost 120 daily high temperature records have been rewritten
Over the past week across the province. Some records have been
shattered by as much as 14 degrees.

Normally we are still feeling the chill of winter's final breath.
But instead, words such as humidex, daffodils and patio weather
Are on everybody's lips. Even across Northern Ontario the snow
Pack has been melting at inconceivable rates. For instance,
Geraldton reported 31 centimetres of snow on the ground on March
18th. Two days later it had virtually all melted.

It appears that this March will likely be the warmest March on
Record for some places. In Toronto (Pearson airport), the previous
record warm March was 1946 with an average temperature of 5.2
Degrees (the average of all high and low temperatures), where
normally the average is -0.4 degrees for Pearson. Given the
Forecast trends for the final days of March, it appears this record
may be handily broken. In fact, March 2012 May go down as the month
with the warmest departure from normal of any month for Toronto,
including downtown where records began in 1840! The hottest March
Day ever recorded at Pearson was 25.6 set back in 1946 on March
28th. This may very well be broken on Thursday of this week.

This warm spell is projected to last until Thursday when a cold
Front will introduce somewhat cooler air (but still above normal) on
Friday.

Below are record maximum temperature records set on Monday
19-mar-2012. Please refer to the table below for more details.

------------------------------------------------- ------------
Location new temperature record previous record

Windsor 23.9 20.6 (1945)
London 22.3 17.8 (2010)
Kitchener-Waterloo 24.0 17.7 (2010)
Hamilton 23.5 16.2 (2010)
Mount Forest 23.0 16.7 (2010)
Wiarton 22.9 12.5 (2010)
Toronto Pearson 22.8 19.1 (2010)
Buttonville 23.3 19.4 (2010)
Barrie 23.3 17.9 (2010)
Borden 25.1 19.7 (2010)
Trenton 21.8 13.9 (1945)
Kingston 18.6 11.6 (2010)
Peterborough 23.4 16.0 (2010)
Muskoka 24.2 15.1 (2010)
Parry Sound 23.6 10.6 (2010)
Algonquin east gate 23.6 12.7 (2010)
Ottawa 24.8 16.0 (2010)
Petawawa 22.4 12.0 (2010)

This weather summary contains preliminary information and may not
constitute an official or final report.

END/OSPC
Member Since: Posts: Comments:
Quoting Jedkins01:



I don't know about good rain, a PWAT of 1.50 is sufficient for some scattered storms given cooler air aloft present because its earlier in the year. However, its not even close to the 2-2.5 inch moisture range in the wet season. That being said 1.50 without any dynamical forcing or low pressure system won't provide drought helping rain. Here on the West Coast of Florida we might get a few decent storms along the sea breeze, but not anything widespread and significant like we need to help the drought.

My front yard is so dry it looks like someone poured gas on it and lit it on fire... lol


Hey, to me a good rain at this point would be a 1/2 inch as it is getting very dry over in Orlando as well due to highs of 84 to 87 for over a week now when normal is 77.
Member Since: Posts: Comments:
Quoting Jedkins01:



Hey man read my post, that estimate is way off...


Rain gauges do not support that much rain. Top rain amounts from gauges are in the 6 to 7 inch range, which is still A LOT of rain, but not 10 to 15 like the radar "thinks".


BTW, looks like I was right about actual rain totals not living up to the huge 6 to 9 inch widespread bulls eye of rain the HPC had for the region the other night. Widespread amounts ended up being 2 to 4 with isolated 5 to to 6, and maybe a bit more in a few local areas.

That's still a crazy of rain, but I knew it wasn't going to be quite as extreme as predicted...


I agree the radar est. seem to always be off the mark. In FL it seems as if the radar always under estimates the precip amounts. Maybe due to the deep tropical moisture that's always around us.
Member Since: Posts: Comments:
Quoting StormTracker2K:
These deep easterly winds have been bailing us out lately. Looks as if some good rain maybe moving into C FL over the next 12 to 24 hours.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
321 PM EDT TUE MAR 20 2012

.DISCUSSION...

...INCREASING RAIN CHANCES LATE TONIGHT (COAST) INTO WEDNESDAY
MORNING...

WED...POTENTIAL WET START TO EARLY PART OF THE DAY AS MODELS SUGGEST
SURGE OF MOISTURE (PWAT`S ~ 1.40-1.50 INCHES) IN THE DEEP SOUTHEASTERLY
FLOW WILL MOVE ACROSS EAST CENTRAL FLORIDA. PRECIPITATION CHANCES
WILL RANGE FROM 30 TO 40 PERCENT WITH GREATER CHANCES ALONG THE
COAST IN THE MORNING SPREADING INLAND THROUGH THE DAY. LOCALLY HEAVY
RAINFALL POSSIBLE ALONG THE SPACE/TREASURE COASTS DURING THE
MORNING. FORECAST SOUNDINGS ARE SLIGHTLY UNSTABLE SO WILL KEEP AN
ISOLATED THUNDERSTORM CHANCE IN THE FORECAST ACROSS THE AREA.
PRECIPITATION CHANCES SHOULD END FROM EAST TO WEST THROUGH THE DAY
AS RAINFALL INCREASES OVER THE WESTERN PENINSULA IN THE AFTERNOON.
ANOTHER BREEZY DAY IN STORE AS EAST-SOUTHEAST WINDS AVERAGE 15 TO 20
MPH WITH HIGHER GUSTS. DESPITE POTENTIAL CLOUD COVER AND PRECIPITATION
MOS GUIDANCE SUGGESTS LOWER 80S FOR HIGHS ALONG THE COAST WITH SOME
SPORADIC MIDDLE 80S OVER THE INTERIOR.




I don't know about good rain, a PWAT of 1.50 is sufficient for some scattered storms given cooler air aloft present because its earlier in the year. However, its not even close to the 2-2.5 inch moisture range in the wet season. That being said 1.50 without any dynamical forcing or low pressure system won't provide drought helping rain. Here on the West Coast of Florida we might get a few decent storms along the sea breeze, but not anything widespread and significant like we need to help the drought.

My front yard is so dry it looks like someone poured gas on it and lit it on fire... lol
Member Since: August 21, 2008 Posts: 0 Comments: 7438
Neapolitan beat me to it ;)


If tomorrow's forecast verifies than the first 21 days of March would not only be well above the March record for Chicago it would tie the rank as the 7th warmest April!
Member Since: March 11, 2012 Posts: 0 Comments: 114
MSNBC on news so far about the Magnitude7.4 Earthquake between Acapulco and Oaxaca
Member Since: Posts: Comments:

Viewing: 186 - 136

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Mostly Cloudy
60 °F
Mostly Cloudy