Tornadoes, extreme flooding, unprecedented heat expected in U.S. today

By: Dr. Jeff Masters , 3:04 PM GMT on March 19, 2012

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Widespread and potentially catastrophic areal flooding and river flooding is expected this afternoon through Wednesday morning in Eastern Oklahoma, Western Arkansas, Western Louisiana, and Southwest Missouri, warns the National Weather Service in Tulsa, Oklahoma, in their latest flood watch for the region. The storm system responsible is a massive, slow-moving trough of low pressure over the Western U.S. that dumped heavy snows that closed several interstate highways in Arizona over the weekend. This storm system will collide 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 yesterday had the highest levels of moisture ever recorded so early in the year, and moisture levels are expected to remain at record levels today. At the boundary between the Western U.S. trough of low pressure and Central U.S. ridge of high pressure, a cold front will lift huge quantities of moisture-laden air aloft, forcing record rains to fall. A wide region of 4 - 8 inches of rain is expected in the flood watch area, and isolated amounts as high as 15 inches could fall by Wednesday, as numerous rounds of thunderstorms repeatedly track over the same area. The cold front is also expected to trigger a Moderate Risk of severe weather over much of Texas today, including the Dallas-Fort Worth area, says NOAA's Storm Prediction Center. Damaging winds, large hail, flash flooding, and few strong tornadoes are expected to affect the area late this afternoon. Severe thunderstorm watches are already posted for much of West Texas, as seen on our Severe Weather Map. Eleven tornadoes were reported yesterday in Oklahoma, Nebraska, and South Dakota.


Figure 1. Predicted rainfall amounts for the 3-day period Monday morning through Thursday morning show an area of 7+ inches (yellow colors) is expected over Eastern Oklahoma, Western Arkansas, Western Louisiana, and Southwest Missouri. Image credit: NOAA HPC.


Figure 2. NOAA's Storm Prediction Center has highlighted a Moderate Risk area for severe weather over much of Texas today, including the Dallas-Fort Worth area.

Summer in March for the Midwest
The ongoing March heat wave in the Midwest is one of the most extreme heat events in U.S. history. With so many records being shattered, it is difficult to cover in detail just how widespread, long-lasting, and extreme the event is, and I offer just a few highlights:

Winner, South Dakota hit 94°F yesterday, the earliest 90°+ reading ever recorded in the Northern Plains, according to wunderground's weather historian, Christopher C. Burt. The 94°F reading was just 2°F short of the all-time state record for South Dakota in March, which was 96°F in Tyndall in 1943. However, subsequent analysis by NOAA questioned this 94°F reading, and it is now believed that 87°F is the appropriate high for Winner.

International Falls, Minnesota hit 79°F yesterday, the hottest March temperature on record in the Nation's Icebox. At midnight this morning, the temperature was 66°F there, breaking the record high for March 19 (set in 1910) by 6°F. The low temperature for International Falls bottomed out near 60°F this morning, so low for today is (unofficially) the same as the previous record high for the date. This is the seventh consecutive day that International Falls has broken 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.

Houghton, Michigan, near the frigid shores of Lake Superior, hit 76°F both Saturday and Sunday. It was the hottest March temperature on record, and an astonishing 44°F above the average high for the date (Saturday) of 32°. Huron, South Dakota also recorded a high temperature (88°F) that was 44° above the average high for the date, on Sunday. Most of the cities in Northern Michigan set all-time March high temperature records over the weekend.

Chicago, Illinois now has a string of five consecutive days of 80°+ temperatures, and the hottest temperature on record for so early in the year (82°F on Friday, and tied again on Saturday). The average high temperature in August is 82°F in Chicago, so this week is basically summer weather. Prior to this year, there had only been 10 days in March with highs in the 80s in Chicago, going back to 1871. The last time Chicago saw an 80 degree temperature during the month of March (prior to this year) was over 22 years ago back on March 12, 1990 when the high temperature hit 81. This morning's Public Information Statement from the National Weather Service in Chicago had this to say about this unprecedented March heat:

Chicago and Rockford have now both broken high temperature records 5 days in a row. There is even the potential they could tie or break record highs for up to an unbelievable 8 days in a row depending on how warm temperatures get Monday through Wednesday. It is extraordinarily rare for climate locations with 100+ year long periods of records to break records day after day after day.


Figure 3. March's month-to-date average temperature compared to the other top 5 warmest months of March in Chicago. The dotted blue lines are month-to-date average temperatures based on the current predicted temperatures. The hashed black line is the average month to date temperature for March. These graphs really illustrate just how far above the previous warmest top 5 Marches this month really has been and assuming no major pattern change the last week of the month gives some indication of just how far above the record March 2012 could end up being. Image credit: NWS Chicago.

Record heat in Canada
Record-breaking heat has also penetrated into the Prairie provinces of Canada over the past week. Winnipeg, Manitoba broke its record high for the past four days in a row, and hit 21°C yesterday, its hottest temperature on record so early in the year. With today's forecast by Environment Canada and wunderground both calling for highs near 25°C (77°F), Winnipeg is likely to record its highest March temperature on record. Previous record: 23.3°C on March 27, 1946. The earliest date for a 25°C+ temperature in Winnipeg is April 9, 1977.


Figure 4. 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. There are at least three large-scale patterns working together right now to create an unusually strong ridge over the eastern half of the U.S.:

1) La Niña. The on-going La Niña event in the Eastern Pacific has weakened considerably over the past month, but ocean temperatures there are still cool enough to affect the jet stream pattern, favoring high pressure and warm temperatures over the Eastern U.S., and low pressure and cold temperatures over the Western U.S.

2) The Madden-Julian Oscillation( MJO). The MJO is a 2-month cycle of thunderstorm activity that travels west to east along the Equator. The MJO is currently in phase with La Niña, and is helping create warmer temperatures over the Eastern U.S.

3) The North Atlantic Oscillation (NAO.) The NAO is in its positive phase, which means the difference in pressure between the Icelandic Low and the Azores High is stronger than usual. This tends to increase the jet stream winds and keeps the jet from sagging southwards over the Eastern U.S.

While the blocking pattern responsible for the heat wave is natural, it is very unlikely that the intensity of the heat would have been so great unless we were in a warming climate. Climate scientist Dr. James Hansen has posted an interesting (as yet unpublished) paper discussing how the odds of such extreme heat events have shifted in recent years.

Extreme jet stream patterns like this often lead to tornado outbreaks in the Midwest, at the boundary of where warm, moist air flowing north from the Gulf of Mexico collides with cold, dry air flowing south. Cold dry air aloft, combined with warm, moist air at the surface, makes the atmosphere unstable, since air rising in thunderstorm updrafts will be less dense than the surroundings, allowing the air to accelerate upwards and increase the intensity of the thunderstorm. This will be the case today, when NOAA's Storm Prediction Center has highlighted a Moderate Risk area for severe weather over much of Texas today, including the Dallas-Fort Worth area.

Flood risk low this year for the Northern Plains
For the first time in four years, the Northern Plains are not expecting major to record snow melt flooding, said NOAA's National Weather Service in their annual spring flood outlook issued last week. Residents along the Mississippi, Missouri, Red, and Souris Rivers have endured a punishing series of bad flood years, but this year is unlikely to continue that trend, due to a lack of snow cover. The Northern Plains states of Minnesota, Wisconsin, North Dakota, and South Dakota recorded their 3rd - 8th warmest winter in the 117-year record, and are on pace to crush the record for warmest March in history. Winter snowfall was below average over most of the region, and what snow was on the ground at the beginning of March has mostly melted, thanks to the record-breaking March heat this week. The Souris and Red River basins contain about one-third the amount of water in the snow as last year, ranking this season in the lower half of the last 60 years. Precipitation this water year (since Oct 1, 2011) has been less than 50% of the normal across the Upper Mississippi and Upper Missouri Valleys, and much of the region is under moderate to severe drought, according to the latest Drought Monitor.


Figure 5. What a difference a year makes! Snow cover on March 15 of last year (top) was heavy over Minnesota, Wisconsin, and the Dakotas, and caused massive flooding problems on the Mississippi and Missouri Rivers during spring melt season. In contrast, there is almost no snow pack in the Upper Midwest this year (bottom), significantly reducing the odds of spring flooding on the Missouri and Mississippi Rivers. Image credit: NOAA/NOHRSC.


Figure 6. The U.S. spring flood risk, as predicted by the National Weather Service on March 15, 2012.

Jeff Masters

March 18th sundown (rosana)
Today it was warm, sunny & calm water with clouds matching the mood of the people just enjoying this view.
March 18th sundown
Mullet Lake ice melting (JeffMasters)
I pulled a piece of ice out of Mullet Lake in Northern Michigan during my bike ride along the shore. It was so strange riding shirtless in 82°F heat along the shore of a frozen lake. The ground still had some snow patches from the 16" snow storm from last week. The lake ice is breaking up weeks ahead of usual due to our warm winter and incredible March heat.
Mullet Lake ice melting
Come have a glass of wine on the patio! (RedRoxx)
LOL woke up to MORE snow, in the VOC (Sedona) are today, want to have a drink on the patio with us?
Come have a glass of wine on the patio!
End of the Icefishing Season (bbend)
One last beautiful day on the ice but it's beginning to weaken and get unsafe- another 60 plus degree day. Normally we'd have about 3' of ice or more but this season it was about 24" at the most.
End of the Icefishing Season

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Made it up to 81 here in Toledo today. That was a new record for the date, and the earliest 80 reading on record. It's supposed to be in the low to mid 80s tomorrow and Wednesday, and upper 70s to near 80 Thursday, so some more records should be broken.
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Once line passes I-35 corridor, it will tap the Gulf and be fully sustained for the ride east.
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Quoting 1900hurricane:
Decided to call my chase. Storms are just too far away for me right now and won't come close enough until it starts getting dark.

You're staying on the safe side
Member Since: November 6, 2010 Posts: 11 Comments: 8133
Possible debris ball.
Member Since: July 22, 2010 Posts: 1 Comments: 3842
The Junction storm is the largest one near the top, with the line of storms SW of the Junction storm also clearly visible with overshooting tops. There are also new storms forming south of there in the Rio Grande area.

Member Since: August 2, 2006 Posts: 46 Comments: 11668

STORM HAZARDS INCLUDE...
DANGEROUS TORNADIC WINDS.
LARGE DAMAGING HAIL UP TO LARGE DAMAGING HAIL UP TO GOLF BALL
SIZE..

Member Since: February 11, 2012 Posts: 83 Comments: 7833
Im getting a hail reading of 3.81in on the cell south of the tornado warned one.
Member Since: July 22, 2010 Posts: 1 Comments: 3842
Quoting RitaEvac:


Quit complaining, and enjoy the water


Lol. Not complaining. :p If we actually do get 7-8 inches I'll need a snorkel to enjoy that water. But last time they called for 7 inches here we barely got a drop. So we'll see.
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I-35 Express about to light up later with a storm Express
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Quoting MississippiWx:


They are saying that days 6-10 in the forecast should have below normal amounts of precipitation in the brown areas. That doesn't account for days 1-5 which should have well above normal amount of precip in a lot of areas.


Technically, no. What it is saying is that the probability of below/above average precip is the labeled contour. So if it shows "40" and "below," that means there is a 40% chance of below average precip and a 60% chance of near average or above average precip.
Member Since: September 28, 2002 Posts: 5 Comments: 3198
Sad story.. surprised a hot air balloon pilot would launch into an unstable atmosphere...
"FITZGERALD, Ga. (AP) — A hot-air balloon pilot found a safe spot for his skydiving passengers to bail out just before a thunderstorm sucked in his craft and sent him plummeting to his death."

Link
Member Since: Posts: Comments:
Decided to call my chase. Storms are just too far away for me right now and won't come close enough until it starts getting dark.
Member Since: August 2, 2006 Posts: 46 Comments: 11668
Quoting RitaEvac:
I expect to see later tonight one gigantic line of intense storms, be a hellava sight on radar.

I have A/C cranked down to 60o. At least the house will be cool when I wake up at 4:30a with no power.
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Quoting redwagon:

Twister on the ground and no SPC red polygrams.


The SPC has had a tornado watch out for that area since before the tornado warning.
Member Since: September 28, 2002 Posts: 5 Comments: 3198
Quoting AtHomeInTX:
WHOA!



Quit complaining, and enjoy the water
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BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SAN ANGELO TX
437 PM CDT MON MAR 19 2012

THE NATIONAL WEATHER SERVICE IN SAN ANGELO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHWESTERN MCCULLOCH COUNTY IN WEST CENTRAL TEXAS...
MENARD COUNTY IN WEST CENTRAL TEXAS...

* UNTIL 515 PM CDT

* AT 435 PM CDT...A SEVERE THUNDERSTORM WAS 8 MILES SOUTHEAST OF FORT
MCKAVETT...OR 21 MILES SOUTHWEST OF MENARD...MOVING NORTHEAST AT 45
MPH.

STORM HAZARDS INCLUDE...
HALF DOLLAR SIZE HAIL.
DAMAGING WINDS IN EXCESS OF 60 MPH.

WITH POSSIBLE STORM IMPACTS...
SOME VEHICLE DENTS...
MINOR ROOF AND PLASTIC SIGN DAMAGE...
A FEW EXPOSED WINDOWS COULD CRACK OR BREAK...
SOME TREE LIMB DAMAGE...WEAKENED TREES TOPPLED...
UNSECURED LIGHT OBJECTS BLOWN AROUND...
SCATTERED POWER OUTAGES POSSIBLE...
POTENTIALLY DEADLY LIGHTNING.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
THE INTERSECTION OF US-190 AND RANCH ROAD 864 BY 445 PM CDT...
THE INTERSECTION OF US-83 AND RANCH ROAD 1773 BY 455 PM CDT...
MENARD AND THE INTERSECTION OF US-83 AND HIGHWAY 29 BY 500 PM
CDT...
US-190 NEAR THE MENARD-MCCULLOCH COUNTY LINE BY 515 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT MONDAY EVENING
FOR WEST CENTRAL TEXAS.

&&

LAT...LON 3071 10011 3084 10011 3109 9977 3110 9960
3097 9944 3071 9987
TIME...MOT...LOC 2137Z 232DEG 40KT 3073 10003

$$
NR
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No chasers I can see on the storm right now but that will change in a hour or less.
Member Since: July 22, 2010 Posts: 1 Comments: 3842
WHOA!

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I expect to see later tonight one gigantic line of intense storms, be a hellava sight on radar.
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Quoting 1900hurricane:
TORNADO WARNING
TXC267-192200-
/O.NEW.KSJT.TO.W.0003.120319T2129Z-120319T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SAN ANGELO TX
429 PM CDT MON MAR 19 2012

THE NATIONAL WEATHER SERVICE IN SAN ANGELO HAS ISSUED A

* TORNADO WARNING FOR...
WESTERN KIMBLE COUNTY IN WEST CENTRAL TEXAS...

* UNTIL 500 PM CDT

* AT 425 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
TORNADO WAS 4 MILES SOUTH OF ROOSEVELT...OR 18 MILES WEST OF
JUNCTION...MOVING EAST NORTHEAST AT 40 MPH.

IN ADDITION TO DANGEROUS TORNADIC WINDS...OTHER HAZARDS INCLUDE...
LARGE DAMAGING HAIL UP TO GOLF BALL SIZE.
POTENTIALLY DEADLY LIGHTNING.

* THE TORNADO IS EXPECTED TO BE NEAR...
JUNCTION BY 450 PM CDT...

THIS INCLUDES INTERSTATE 10 BETWEEN MILE MARKERS 429 AND 450.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT MONDAY EVENING
FOR WEST CENTRAL TEXAS.

&&

LAT...LON 3051 10011 3064 9979 3037 9971 3034 10011
TIME...MOT...LOC 2129Z 250DEG 36KT 3044 10002

$$

Twister on the ground and no SPC red polygrams.
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Quoting TropicalAnalystwx13:
Tight rotation with this storm...likely tornado.

You can really see the inflow in the storm. Puts a large notch into it.
Member Since: July 22, 2010 Posts: 1 Comments: 3842
Looks like some storms are starting to fire in front of the original boundry SW of San Antonio and near Eagle Pass.



Member Since: August 2, 2006 Posts: 46 Comments: 11668
Tight rotation with this storm...likely tornado.

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SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
424 PM CDT MON MAR 19 2012

IAC039-053-159-192134-
/O.EXP.KDMX.SV.W.0001.000000T0000Z-120319T2130Z/
RINGGOLD IA-CLARKE IA-DECATUR IA-
424 PM CDT MON MAR 19 2012

...THE SEVERE THUNDERSTORM WARNING FOR DECATUR...SOUTHERN CLARKE AND
EASTERN RINGGOLD COUNTIES WILL EXPIRE AT 430 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.

LAT...LON 4058 9408 4090 9404 4090 9402 4107 9401
4096 9356 4092 9356 4057 9382
TIME...MOT...LOC 2124Z 201DEG 41KT 4091 9384

$$

AWB
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Quoting RitaEvac:
Event hasn't even begun and Houston already losing power to high winds
Thanks for the heads-up Rita. Time to fire the genny up and get her ready before the worst gets here. Just got home from work, catching up on the action.
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TORNADO WARNING
TXC267-192200-
/O.NEW.KSJT.TO.W.0003.120319T2129Z-120319T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SAN ANGELO TX
429 PM CDT MON MAR 19 2012

THE NATIONAL WEATHER SERVICE IN SAN ANGELO HAS ISSUED A

* TORNADO WARNING FOR...
WESTERN KIMBLE COUNTY IN WEST CENTRAL TEXAS...

* UNTIL 500 PM CDT

* AT 425 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
TORNADO WAS 4 MILES SOUTH OF ROOSEVELT...OR 18 MILES WEST OF
JUNCTION...MOVING EAST NORTHEAST AT 40 MPH.

IN ADDITION TO DANGEROUS TORNADIC WINDS...OTHER HAZARDS INCLUDE...
LARGE DAMAGING HAIL UP TO GOLF BALL SIZE.
POTENTIALLY DEADLY LIGHTNING.

* THE TORNADO IS EXPECTED TO BE NEAR...
JUNCTION BY 450 PM CDT...

THIS INCLUDES INTERSTATE 10 BETWEEN MILE MARKERS 429 AND 450.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT MONDAY EVENING
FOR WEST CENTRAL TEXAS.

&&

LAT...LON 3051 10011 3064 9979 3037 9971 3034 10011
TIME...MOT...LOC 2129Z 250DEG 36KT 3044 10002

$$
Member Since: August 2, 2006 Posts: 46 Comments: 11668
Member Since: November 6, 2010 Posts: 11 Comments: 8133
San Antonio keep an eye to your SW
Member Since: Posts: Comments:
Quoting TomTaylor:
Awesome pics Aussie
Quoting TomTaylor:
Awesome pics Aussie

Yeah, wonderful pics
Member Since: November 6, 2010 Posts: 11 Comments: 8133
Something Important for you Hurricane chasers:NOUS41 KWBC 011848
PNSWSH

Public Information Statement
National Weather Service Headquarters Washington DC
148 PM EST Thu Mar 1 2012

To: Subscribers:
-Family of Services
-NOAA Weather Wire Service
-Emergency Managers Weather Information Network
-NOAAPORT
Other NWS partners and NWS employees

From: Mark Tew
Chief, Marine and Coastal Services Branch

Subject: Minor Modification of Saffir-Simpson Hurricane Wind
Scale Thresholds Effective May 15, 2012

Effective May 15, 2012, the Saffir-Simpson Hurricane Wind Scale
(SSHWS) will be adjusted slightly to resolve issues associated
with the conversion of units used for wind speed. This change
follows a public comment period conducted in 2011.

The National Hurricane Center (NHC) and Central Pacific Hurricane
(CPHC) assign intensities of hurricanes in 5-knot (kt)
increments. For advisory products, these intensities are
converted to miles per hour (mph) and kilometers per hour (km/h),
and then rounded to the nearest 5-mph or 5-km/h increments.
Challenges occur when the current Category 4 intensity is 115 kt
(132.3 mph). Although 115 kt is within the Category 4 range, the
equivalent rounded wind speed in mph is 130 mph, which is in the
Category 3 range. To classify the hurricane as a Category 4 in
both sets of units (kt and mph), NHC and CPHC must incorrectly
convert 115 kt to 135 mph in the advisory products. A similar
issue occurs when the current Category 4 intensity of 135 kt is
converted to km/h.

Effective May 15, 2012, to resolve these rounding issues,
Category 4 on the SSHWS will be broadened by one mph at each end
of the range, yielding a new range of 130-156 mph. This will
also result in a minor modification of the Category 3 and 5 wind
speed thresholds. The SSHWS will change as follows:

From:

Category 3: 111-130 mph (96-113 kt, 178-209 km/h)
Category 4: 131-155 mph (114-135 kt, 210-249 km/h)
Category 5: 156 mph or higher (136 kt or higher, 250 km/h or
higher)

To:

Category 3: 111-129 mph (96-112 kt, 178-208 km/h)
Category 4: 130-156 mph (113-136 kt, 209-251 km/h)
Category 5: 157 mph or higher (137 kt or higher, 252 km/h or
higher)

There will be no change to the wind speeds currently assigned to
Categories 1 and 2.

With this change, a 115-kt Category 4 hurricane will have its
intensity properly converted to mph and rounded to the nearest 5
mph (130 mph) and remain within the Category 4 mph range.

Important note: Since intensities are assigned using 5-kt
increments, neither storms in the historical record nor any
future storms will have their SSHWS category changed as a result
of this modification to the scale.

The NWS wishes to remind media, partners, and the public the
Saffir-Simpson Hurricane Wind Scale provides information on wind
impacts only. The scale does not provide commentary or
information on other impacts or characteristics of tropical
cyclones.

Additional information on this change can be found at:

http://www.nhc.noaa.gov/aboutsshws.php

If you have any questions, please contact

John Kuhn
National Weather Service
Silver Spring, Maryland 20910
301 713 1677 ext. 121
john.f.kuhn@noaa.gov

National Public Information Notices are online at:

http://www.weather.gov/om/notif.htm

$$

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Member Since: July 22, 2010 Posts: 1 Comments: 3842
Quoting TropicalAnalystwx13:

Possibly. It would have to be a dry microburst though, and not a wet one.


JAWS at airports should report what it was shortly, if it was microbursts.
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Toronto Pearson Int'l Airport
Date: 5:00 PM EDT Monday 19 March 2012
Condition: Mainly Sunny
Pressure: 30.12 inches
Tendency: falling
Visibility: 15 miles
Air Quality Health Index: 4

Temperature: 72.5°F
Dewpoint: 55.9°F
Humidity: 56 %
Wind: SSE 5 mph
Humidex: 78

Normals
Max: 43°F
Min: 27°F
Member Since: Posts: Comments:
SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 86
NWS STORM PREDICTION CENTER NORMAN OK
420 PM CDT MON MAR 19 2012

SEVERE THUNDERSTORM WATCH 86 IS IN EFFECT UNTIL 1200 AM CDT
FOR THE FOLLOWING LOCATIONS

OKC001-005-013-021-023-029-061-069-077-079-085-09 1-095-101-121-
127-135-200500-
/O.NEW.KWNS.SV.A.0086.120319T2120Z-120320T0500Z/

OK
. OKLAHOMA COUNTIES INCLUDED ARE

ADAIR ATOKA BRYAN
CHEROKEE CHOCTAW COAL
HASKELL JOHNSTON LATIMER
LE FLORE LOVE MARSHALL
MCINTOSH MUSKOGEE PITTSBURG
PUSHMATAHA SEQUOYAH
$$


ATTN...WFO...TSA...OUN...
Member Since: August 2, 2006 Posts: 46 Comments: 11668
Quoting MAweatherboy1:
Severe Thunderstorm watch 86 to be issued momentarily



URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 86
NWS STORM PREDICTION CENTER NORMAN OK
420 PM CDT MON MAR 19 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

NORTHWEST ARKANSAS
EASTERN OKLAHOMA

EFFECTIVE THIS MONDAY AFTERNOON FROM 420 PM UNTIL MIDNIGHT CDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 50
STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES SOUTH
SOUTHWEST OF DURANT OKLAHOMA TO 35 MILES NORTH NORTHEAST OF
FAYETTEVILLE ARKANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 85...

DISCUSSION...INTENSE THUNDERSTORMS OVER NORTH TX WILL TRACK
NORTHEASTWARD ALONG SURFACE BOUNDARY INTO EASTERN OK AND EVENTUALLY
INTO NORTHWEST AR THIS EVENING. STORMS THUS FAR HAVE BEEN SLIGHTLY
ON THE COOL SIDE OF THE BOUNDARY...WITH BOW/LEWP STRUCTURES CAPABLE
OF DAMAGING WINDS AND HAIL. CONDITIONS WILL BE CLOSELY MONITORED
FOR ACTIVITY FORMING IN THE WARM SECTOR...WHERE STRONG LOW LEVEL
SHEAR WOULD REQUIRE AN UPGRADE TO TORNADO WATCH.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 23035.


...HART
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Severe Thunderstorm watch 86 to be issued momentarily
Member Since: February 11, 2012 Posts: 83 Comments: 7833
Quoting redwagon:


Microbursts?

Possibly. It would have to be a dry microburst though, and not a wet one.
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Quoting redwagon:

You're in Cedar Park, I'm right next to you in Volente.

Howdy, neighbor!
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Quoting muddertracker:

Hey RitaEvac,

Where can I go to see the CAP values for Central Texas? TIA

You're in Cedar Park, I'm right next to you in Volente.
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Quoting AussieStorm:
Some awesome Lightning photo's from a storm near Geelong, Victoria.










Link
Awesome pics Aussie
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Quoting TropicalAnalystwx13:
There have been multiple reports of structural damage and tractor trailers being flipped in Dallas...non-severe thunderstorm winds at that.


Microbursts?
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Quoting RitaEvac:
Bad weather coming when you have inflow winds gusting over 40+mph

Hey RitaEvac,

Where can I go to see the CAP values for Central Texas? TIA
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Quoting TropicalAnalystwx13:
There have been multiple reports of structural damage and tractor trailers being flipped in Dallas...non-severe thunderstorm winds at that.

That's not sounding too good
Member Since: November 6, 2010 Posts: 11 Comments: 8133
Bad weather coming when you have inflow winds gusting over 40+mph
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There have been multiple reports of structural damage and tractor trailers being flipped in Dallas...non-severe thunderstorm winds at that.
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Scholes Airport in Galveston reporting 45mph gust from a weatherbug station
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Tornadic cell heading for Junction, TX
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Storm west of Junction looks like it's trying to become a right-mover.

Member Since: August 2, 2006 Posts: 46 Comments: 11668
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CLEVELAND OH
453 PM EDT MON MAR 19 2012

OHC033-139-192115-
/O.CON.KCLE.SV.W.0022.000000T0000Z-120319T2115Z/
CRAWFORD OH-RICHLAND OH-
453 PM EDT MON MAR 19 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR CENTRAL RICHLAND AND SOUTHEASTERN CRAWFORD COUNTIES IN NORTH
CENTRAL OHIO...

AT 445 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED
6 MILES NORTHWEST OF MANSFIELD...MOVING EAST AT 25 MPH.

LOCATIONS NEAR THE PATH OF THE SEVERE THUNDERSTORM INCLUDE...RURAL
EASTERN RICHLAND COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

INCH AND A QUARTER SIZE HAIL HAS BEEN REPORTED IN CRESTLINE WITH
THIS STORM. IF YOU ARE IN THE PATH OF THE STORM...TAKE IMMEDIATE
ACTION TO PROTECT LIFE AND PROPERTY.

&&

LAT...LON 4069 8262 4071 8263 4071 8272 4072 8278
4083 8281 4084 8276 4089 8243 4067 8240
TIME...MOT...LOC 2053Z 253DEG 23KT 4083 8255

$$

WILLARD
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The tornado warned cell seems to have a similar radar presentation to the one last night.
Member Since: July 22, 2010 Posts: 1 Comments: 3842

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

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