North American Mesoscale Model Verification on January 26-27...

By: Zachary Labe , 10:34 PM GMT on January 29, 2011

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The North American Mesoscale Model (NAM) is a high resolution model courtesy of the National Center for Environmental Prediction. Another very common and referenced name for the model is the Weather Research and Forecasting Model (WRF). They are the same model and run out to 84 hours. The purpose of the model is to run a higher resolution determining mesoscale features that often cannot be picked up by the global models due to their larger scale. The NAM can be run on an 80km resolution with a broad view of the United States, or 40km which allows the viewer to zoom in on a localized region to put up on mesoscale features. Also a very high resolution form of the NAM exists using a 12km parametric and can zoom into different states. The model is released four times a day at 0z, 6z, 12z, and 18z. Keep in mind that time is zulu or more commonly known as greenwich mean time.

Computer models are critical to forecasting the weather as they use parametric and other mathematical equations to derive the current and predicted state of the atmosphere using a physical and chemical explanation as the background for the predictions. The NCEP is associated with the National Oceanic Atmospheric Administration (NOAA) to be the developer of these computer models. Each meteorological organization worlwide uses their own developed computer models to serve as a basis for the forecasts. Without computer models, we are not able to derive predictions on the weather greater than 24 hours out.

Like all computer models, the NAM shows all layers of the atmosphere in maps determining positioning and speed of the jet stream, surface precipitation amounts (quantitive precipitation forecast QPF), temperatures throughout the entire core of the atmosphere, convective indices, simulated radars, etc. Due to the higher resolution of the NAM, several problems do exist. It often produces convective elements in many middle latitude cyclones and these are known as convective feedback problems. This is where it developed these unstable regions and often associates them as surface lows causing the surface depiction to be distorted. This was a problem in the recent prediction of the January 26-27 winter storm and will be noted below. Also the NAM has a tendency to produce higher than normal precipitation amounts. I typically find myself cutting totals nearly by 30% as shown on the NAM. Finally the NAM has a bias to overamplify a low pressure and close them off to early particularily on eastern United States cyclogenesis off the coast.

The January 26-27 winter storm featured many model headaches do to some interesting variables. Early on it appeared likely for a low pressure to track up inland along the coastal plain. There was a lacking 50/50 low, unfavorable position of the western trough axis, neutral NAO, natural baroclinicity along the coastline, and stale antecedent cold air mass. This would produce rain along I-95 with heavy snows inland. The 500mb synoptic pattern showed very strong signals for this time of setup with most computer model guidance also in support. The GGEM and ECMWF led the pack with the heavy snows from I-81 on westward. The GFS suffered major problems with varying solutions for each run. But then the computer models began to delay the storm. In fact it was delayed nearly 48-60 hours from the original starting time. This caused a different scenario to unfold. The lacking high pressure to the north was still a problem as the anticyclone zoomed east-northeast, but now a high pressure and associated shortwave out ahead of it allowed sunk east-southeast across the Midwest and western Great Lakes. This acted as a 'kicker' helping to push the cyclonegenesis farther off the coast. This in turn allowed for a colder scenario along with precipitation to occur farther east. Therefore a turn of events allowed for a major I-95 snowstorm with 6in+ totals from Washington DC to Boston. This was very fortunate for snow lovers in that corridor due to pure luck given the poor synoptic setup.

Given the NAM's high resolution, it often overanalyzes prognostics post hour 60. It tends to enhance QPF, overamplify lows, and pick up on mesoscale features that really do not exist. Therefore I typically throw out hours 60-84. It would be a rare event where you would find the NAM 84 hour verifying anywhere close to accurate. But in the near term range, the NAM does an excellent job locating temperature thermals, QPF ranges, and picking up on mesoscale features; coastal fronts, enhanced convection, deformation bands, etc. But in this recent storm, it suffered a plethora of problems and even the 6 and 12 hour surface maps had poor verification especially in the QPF department.

Let us first look at the actual accumulated precipitation totals for the storm.

Given this is a 24 hour accumulated precipitation amount, about .01-.1in of additional precipitation fell south of the Mason-Dixon line in the previous 24 hours.

Here are the preceeding NAM total QPF forecasts...


(January 24; 18z) (January 25; 6z)


(January 25; 12z) (January 25; 18z)


(January 26; 0z) (January 26; 6z)

As you can see, the NAM had a lot of variance with the northwestern sharp precipitation gradients. These tight gradients this year have been caused by the rapid intensification of the coastal lows allowing the heaviest moisture to be confined closer to the center of circulation. Also in this instance, a very cold and dry air mass along with associated cold front was quickly advancing southeast across the Great Lakes and was even picked up on by the 700mb RH charts. This allowed the flow out of the northwest to dry up some moisture for areas more inland.

The NAM simulated radar vs. the forecast QPF did not match up. Often the NAM simulated radar showed the heavier mesoscale bands lining up in northern Maryland and southern Pennsylvania where as it only showed total QPF to be .25in-.5in. In fact looking at total verification, the NAM did very well for its simulated radar.


(Actual NEXRAD National Radar) (6z NAM January 26 Simulated Radar)

The NAM did seem to have a hold on the 500mb map showing the negatively tilted trough producing the coastal low along with the placement of the upper level low and associated shortwave kicker just to the west.


(18z NAM January 24; 500mb) (0z NAM January 26; 500mb)

In general the differences in the 500mb maps were very subtle with just a general strengthening in the closed 500mb low, which verified a tad north of the January 24 18z model run.

The NAM did a very excellent job in identifying mesoscale band using the UUV/700mb RH charts.

(6z NAM January 26; 700mb)

It indentifed the enhanced snow growth over southeastern Pennsylvania up through New Jersey and New York City. The problems with the NAM generally existed in the QPF fields. The model likely suffered a very convective feedback issues in QPF totals. This is why it is important to note other maps than surface maps to help locate the heaviest precipitation. The 700mb map screamed that snow totals would be farther inland with the enhanced deformation band and UUV rates. In general the high resolution models handled this the best with the HRR scoring an amazing victory for QPF along with the ECMWF. The GFS/NAM did a very poor job for QPF, but as noted above QPF does not always tell the story. Sometimes it is important to note other layers of the atmosphere to help make a forecast. This point is why many forecasters missed the boat. Many forecasters (especially broadcoast meteorologists) are drawn to the easy to understand QPF/surface maps, but one has to look at all layers of the atmosphere to make a prediction.

Lower Susquehanna Valley Doppler...

(Courtesy of WGAL)

"Here northeast of Harrisburg 2010-2011 winter statistics"
(Snow Stats)
Current Snow Cover- 0-3in
Monthly Total (November)- Trace
Monthly Total (December)- 0.6in
Monthly Total (January)- 18.90in
Monthly Total (February)- 1.35in
Seasonal Total- 20.85in
Winter Weather Advisories- 7
Winter Storm Warnings- 2
Ice Storm Warnings- 0
Blizzard Warnings- 0
Freezing Rain Advisories- 1
Winter Storm Watches- 2

(Temperature Stats)
Lowest High Temperature- 23.7F
Lowest Low Temperature- -1.7F
Wind Chill Advisories- 0
Wind Chill Warnings- 0

(Snow Storms Stats)
First accumulating snow - December 10 - 0.50in of snow
Clipper light snow - January 7-8 - 2.25in then another 1in of snow
Double Barrel Low - January 11 - 4.5in of snow
Coastal Low - January 17-17 - 1.8in of snow/sleet
Arctic Front - January 20-21 - 2.1in of snow
Upper level/coastal low - January 26 - 5.75in of snow
Two clippers - January 28-29 - 1.5in of snow

Ice Storm 2011... (Blizzard92)
.4-.5in of freezing rain
Ice Storm 2011...
Ice Storm 2011... (Blizzard92)
.4-.5in of freezing rain
Ice Storm 2011...
Ice Storm 2011... (Blizzard92)
.4-.5in of freezing rain
Ice Storm 2011...
Ice Storm 2011... (Blizzard92)
.4-.5in of freezing rain
Ice Storm 2011...
Ice Storm 2011... (Blizzard92)
.4-.5in of freezing rain
Ice Storm 2011...
Ice Storm 2011... (Blizzard92)
.4-.5in of freezing rain
Ice Storm 2011...
Ice Storm 2011 (Blizzard92)
Melting begins...
Ice Storm 2011
Ice Storm 2011 (Blizzard92)
Melting begins...
Ice Storm 2011

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Just came in from raking. 57 here right now. Sedum is growing, min.roses have new leaves, weeds are growing! Buds on my lilacs (tiny) and azaleas. Spring must be around the corner! Can't wait to see what else as I move more leaves!
Thanks RP-I am a little anxious! I know it is to early but fun to think about it!
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1266. hurigo
Hey Blizz, et al.
NWS says we'll have snow (snow/rain mix) starting Wed night, Thursday and Thursday night. Hope it stays warm enough. Saw a field of robins today don't know if they've come up from south or down from north. Also saw an osprey coming in to land and making a lot of racket. I think the birds are ready and I know I am too for spring
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Quoting PhillySnow:
We do have a slight chance of show Tuesday morning, LT. Temps are questionable, though what's interesting is how cold it gets later on Tuesday and there's a chance of snow after 3pm also. Is there any hope with the timing of this?


I'm still trying to figure out why all the local mets put us (SE PA) above freezing all night, while the models seem to suggest way otherwise with the freezing line about 100 miles south of Philly around midnight... They (the models) can't be that far off this close to this event (such as it may be), can they? Who do you trust?
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We do have a slight chance of show Tuesday morning, LT. Temps are questionable, though what's interesting is how cold it gets later on Tuesday and there's a chance of snow after 3pm also. Is there any hope with the timing of this?
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The GFS has a strong low about 150 miles ESE of Cape Cod, by 7AM EST. tues AM.
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Wow, there sure is alot of Precip over North Florida and Georgia and it appears to be moving NE up the coast, then one sees that cold front draped along the Ohio Valley moving Eastward. This combination may be the "surprise" Blizz was alluding to yesterday!, for Tues. AM.
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Quoting MarylandGirl:
Well Blizz, listening to local mets I keep hearing..maybe warmer...then not so...maybe snow...then not so.
I am ready for spring and gardening! Sunny and warmer weather. We will all still be here chatting with you.

RP.when can we start planting?


it depends on what you want to plant. onions - for you i would say early March. the hardest part is preparing the soil. Usually early March the soil is still so wet. Also, spinach and lettuce can be started from seed at that time. you can propably put in a few cloves of garlic, even though they get a larger bulb when planted in November. i am not sure if brocolli and cauliflower for early March for you, MG. you might have to wait until the end of March - the book I have says 3-4 weeks before your last frost.
Member Since: January 26, 2007 Posts: 72 Comments: 6233
Well Blizz, listening to local mets I keep hearing..maybe warmer...then not so...maybe snow...then not so.
I am ready for spring and gardening! Sunny and warmer weather. We will all still be here chatting with you.

RP.when can we start planting?
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BTW - I think I figured out Blizz's annoucement. He found the cure for the common cold. HURRAY. I am tired of the one he gave me.
Member Since: January 26, 2007 Posts: 72 Comments: 6233
Quoting pittsburghnurse:
If there are any March storms that plan on making their presence known this far west, please let me know. My moving plans are for St. Patrick's Day weekend, and while I'm not moving far, moving in stormy conditions would give me reason to change the date.

As always I know these things may or may not pan out. I would think maybe we would be spared this far west.


it's not out of the ordinary, though. In 2007 we got like 7" around St. Patricks Day. I was having a one year birthday party for my son with whole family (aunts, uncles and cousins) and half of them cancelled out because of the snow. so it can happen. hmmmmmm. i believe a couple of years before that we got 4 or 5 inches in the beginning of April. come mid-March I would hope we are done with snow.
Member Since: January 26, 2007 Posts: 72 Comments: 6233
Birdsong here this morning! Sunny warmth yesterday was fun; it just seems way too early. My husband and I are looking at real estate in the Adirondacks & Vermont - very affordable and what beautiful places!

I'll stick around in the blog this year. I'm interested in the weather analyses even though I never seem to have time to learn how to do it myself. Plus, I've gotten used to "chatting" with you fine folks each day. :)
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If there are any March storms that plan on making their presence known this far west, please let me know. My moving plans are for St. Patrick's Day weekend, and while I'm not moving far, moving in stormy conditions would give me reason to change the date.

As always I know these things may or may not pan out. I would think maybe we would be spared this far west.
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Luckily no sudden warm-ups are in sight along with sudden rain storms. This means the warmer weather will help for a slow, but steady melting snow without the threat of flooding rain.
Member Since: December 14, 2007 Posts: 278 Comments: 15045
Sounds good to me LT.
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Well, I guess, in laymans terms, this arctic high moving in Tues was or will be too strong and push that low out to sea, despite the La Nina based strengthening SE high pressure system, which in theory would have pushed the storm up the coast or even inland up the coast. Sometimes things just don't do what in theory they should do. That's what makes meteorology so facinating. Sorry there will be no end of week storm, but I am looking foreward to milder weather. Just hope we all don't experience flooding with the melting snow, if it gets too mild too fast. And Blizz said March could be cold and stormy, hum...blizzard of 1888 or Super Storm of '93 anyone?!
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Quoting pittsburghnurse:


Even home girl messed up the anthem. That was the worst moment IMHO. >

Right, yikes. But at least we know she was actually singing. So many others just lip sync these days!
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Quoting TheF1Man:
Well Pittsburghnurse...it was a great season. I know tomlin will have them ready next year


Even home girl messed up the anthem. That was the worst moment IMHO. Aaron Rodgers and company deserve that trophy.

Now what's this about a cold and stormy early Spring? Say it aint so.
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Well Pittsburghnurse...it was a great season. I know tomlin will have them ready next year
Member Since: February 23, 2010 Posts: 0 Comments: 669
Quoting Blizzard92:
Unfortunately (for those hoping for Spring) given the strong La Nina, I would expect a cold and stormy March and April.


woh woh woh Blizz. just a few weeks ago you were calling for warmer than normal March and April. now you can't go back on that prediction/forecast. Na ah. no way, Bud. take it back right now hahahahaha
Member Since: January 26, 2007 Posts: 72 Comments: 6233
Unfortunately (for those hoping for Spring) given the strong La Nina, I would expect a cold and stormy March and April.
Member Since: December 14, 2007 Posts: 278 Comments: 15045
So, is this really the end.....I am almost hopeful, yet regretful...not sure...I would love one more "big one", BUT would also like to get on with Spring and walking in sneakers---good-bye Ugg Boots!
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Nothing but rain in the forecast and that tiny chance for snow that gradually dies the more you keep checking. Ugh.

How about next winter Blizz? Lol.
Member Since: August 28, 2008 Posts: 79 Comments: 3320
1242. anduril
So if the winter is normally a bust (due to higher temps) during La Nina how does the summer typically compare? Warmer? Colder? Do we have a higher chance of thunderstorms? :)
Member Since: August 29, 2006 Posts: 0 Comments: 168
If I recall Zack, in your winter forecast you predicted an early end to winter, as did some other respected mets. So I'm really not surprised.

There are buds on the maples. The snow has turned to slop and we're getting more ice and rain. Birdsong a little more active. Our snowpack (or ice rink) that was firmly established for over a month is 1/2 gone. Signs of the times without the use of models; sans hard science. Just look around. Winter's not over but it's got its walking papers.

Have every intention of hanging around for Spring storm season.
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Quoting TheRasberryPatch:


The pattern is changing that much, huh? so if we get less than 6" of snow for the rest of the year we are below average for snow for the LSV? Isn't that typical for La Nina? but yet again we didn't miss out on heavy snow by much. 100 miles?

you know I will be here. it's almost time to start talking about getting the gardens ready. last fall you said that you were redoing your gardens. any plans yet what you have in mind? plan on planting anything different?

It will be quite warm next week! The pattern upcoming is very remniscent to what this whole winter should have looked like given the strong La Nina. It will be very hard to get snow, especially for eastern areas.

Yes, we were planning to remove the swingset and expand the vegetable garden this area. We have not talked about this in a while, but I still think we are thinking about it. I do not want to plant anything different, but moreso allow the plants to have more room. I always plant them so close together.
Member Since: December 14, 2007 Posts: 278 Comments: 15045
its looking better for us in eastern nc for snow on thursday i see what your talking about with the pattern change people are going to be shocked for me im stoked i cant wait to get out of this wetsuit
Quoting Blizzard92:
Looks like the western track will not occur for the end of the week storm. Tuesday should not be too big of a deal, but I cannot rule out some 1-3in amounts northwest of I-95. It is sort of an arctic front, so a few flash freezes are possible Tuesday with gusty winds. Temperatures will be warming towards the weekend with a lengthy pattern change coming for February. I guess this means 50% of the bloggers here only for winter will slowly be disappearing, lol.
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Quoting Blizzard92:
Looks like the western track will not occur for the end of the week storm. Tuesday should not be too big of a deal, but I cannot rule out some 1-3in amounts northwest of I-95. It is sort of an arctic front, so a few flash freezes are possible Tuesday with gusty winds. Temperatures will be warming towards the weekend with a lengthy pattern change coming for February. I guess this means 50% of the bloggers here only for winter will slowly be disappearing, lol.

Blizz---Time for you snow lovers to move north. Cornell is a good start! Another foot of snow last night with some impressive thundersnow. Lots of lightning with heavy snow is amazing. We are due for at least another 6" over the next two days up here with maybe more due to upslope on the western slopes of the northern Green Mountains. Smugglers Notch resort has reported over 210" this season already! Skis at the ready again.
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Quoting Blizzard92:
Looks like the western track will not occur for the end of the week storm. Tuesday should not be too big of a deal, but I cannot rule out some 1-3in amounts northwest of I-95. It is sort of an arctic front, so a few flash freezes are possible Tuesday with gusty winds. Temperatures will be warming towards the weekend with a lengthy pattern change coming for February. I guess this means 50% of the bloggers here only for winter will slowly be disappearing, lol.


The pattern is changing that much, huh? so if we get less than 6" of snow for the rest of the year we are below average for snow for the LSV? Isn't that typical for La Nina? but yet again we didn't miss out on heavy snow by much. 100 miles?

you know I will be here. it's almost time to start talking about getting the gardens ready. last fall you said that you were redoing your gardens. any plans yet what you have in mind? plan on planting anything different?
Member Since: January 26, 2007 Posts: 72 Comments: 6233
Looks like the western track will not occur for the end of the week storm. Tuesday should not be too big of a deal, but I cannot rule out some 1-3in amounts northwest of I-95. It is sort of an arctic front, so a few flash freezes are possible Tuesday with gusty winds. Temperatures will be warming towards the weekend with a lengthy pattern change coming for February. I guess this means 50% of the bloggers here only for winter will slowly be disappearing, lol.
Member Since: December 14, 2007 Posts: 278 Comments: 15045
Quoting Blizzard92:
Sorry, I won't be able to get a new blog out today; maybe tomorrow.... It will focus on the long range and possible very warm weather approaching the region. My excitment for this week is dwindling fast.


did you say warm up? very warm weather? would that remove most of the snow? Just remember it's February and it only takes one storm up the coast, just like last year.
Member Since: January 26, 2007 Posts: 72 Comments: 6233
Sorry, I won't be able to get a new blog out today; maybe tomorrow.... It will focus on the long range and possible very warm weather approaching the region. My excitment for this week is dwindling fast.
Member Since: December 14, 2007 Posts: 278 Comments: 15045
1233. Matlack
Quoting anduril:
If the Serial to USB doesnt work newegg had a Roswell dual serial port PCI card for pretty cheap the other day


I had to download a driver but it is working now on the old PC RS232 to USB, I had to change the comm port to accomodate the USB comm port - data looks good and is going out to WU and my personal site.
Member Since: January 1, 2006 Posts: 0 Comments: 358
1232. anduril
Quoting Matlack:


WooHoo found a gender bender RS-232 to USB in my cable pile. Now I just need my software upgrade from Ambient....
If the Serial to USB doesnt work newegg had a Roswell dual serial port PCI card for pretty cheap the other day
Member Since: August 29, 2006 Posts: 0 Comments: 168
yes thank you testbenchdude
Member Since: January 26, 2007 Posts: 72 Comments: 6233
Quoting TheRasberryPatch:


I also thought that the air isn't as dense the higher you go in this atmosphere. and i thought it had to do with pressures the higher you go as well. it's been over 20 years since I took Physical Geography. I recall some parts of Earth's atmosphere heats up the higher you go and some are cold


Is this what you're thinking of?

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1229. baba17

Henry Margusity over at the other site pretty much throwing in the towel on winter. Talks of some snow followed by 60 degree days. Even talks about heat waves....huh???????...it's still early Feb.....
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Quoting TrentonThunder:


You'd be surprised at how fast the temperatures fall from 6 Ft above ground to ground level at night. That's why we can have an official air temperature of 37F and have ice on the grass. The temperature has dropped 5F in that 6 feet. That's why they have the standard 2M or 5 - 6 ft temperature measurement guidlines.

It's just the opposite during the day that it will be warmer at ground level than it is at 2M as the sun is radiating off the ground and you're closer to the source of the heat. I'm sure you know, but for those who don't, it's not the sun's rays that are coming down and heating the air. It's the sun's rays coming down that heat the ground/surface of the earth and radiates back up and heats us from there. That's why (mostly during daylight hours) it's colder on mountain tops (farther from the heat source) than it is at low elevations (closer to the heat source). Some wonder why it's not warmer at the top of a mountain seeing that it's closer to the sun. That's the reason...


I also thought that the air isn't as dense the higher you go in this atmosphere. and i thought it had to do with pressures the higher you go as well. it's been over 20 years since I took Physical Geography. I recall some parts of Earth's atmosphere heats up the higher you go and some are cold
Member Since: January 26, 2007 Posts: 72 Comments: 6233
1227. Matlack
Quoting Matlack:


Unfortunately my station is about 6 years old, an Oregon Sceientific WMR968 and uses a RS-232 cable to connect. I guess I'll have to keep the old PC running to keep the station data flowing.


WooHoo found a gender bender RS-232 to USB in my cable pile. Now I just need my software upgrade from Ambient....
Member Since: January 1, 2006 Posts: 0 Comments: 358
1226. Matlack
Quoting TheRasberryPatch:


my Davis Vantage Pro is a USB connector. I have had that for 4 years now and 2 computers. I use VWS from Ambient Weather. I have had no problems. Doesn't your weather station have a USB connection?

wow, about Christmas decorations. I got lucky with the weather this year. some years you wonder how long you might have the outside decorations up.


Unfortunately my station is about 6 years old, an Oregon Sceientific WMR968 and uses a RS-232 cable to connect. I guess I'll have to keep the old PC running to keep the station data flowing.
Member Since: January 1, 2006 Posts: 0 Comments: 358
Everything outside is drip...drip...drip...

8" snowpack with no sign of grass this morning. If we can hang on to 1" snow cover until tomorrow, which I think we will, we will have had an uninterpupted snowpack for 1 month exactly. Only happens once in a while here. Signs of snow have been around since December 26th (drifts, snowpiles etc...)
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Quoting TheRasberryPatch:
what will I be looking for Blizz? and just one eye? hmmmmmmmm are we getting the $100? hahahaha the nws has 41F and rain for that time

i have one for you....when i got home last night just before 2am the temp on my weather station (@ 11 feet above ground) was reading 37F. The water on my driveway had already started to freeze and made it like a skating rink with slushy areas. I am guessing the temp at ground level was lower and the winds were helping the water to freeze. I was surprised with temp that high at my station


You'd be surprised at how fast the temperatures fall from 6 Ft above ground to ground level at night. That's why we can have an official air temperature of 37F and have ice on the grass. The temperature has dropped 5F in that 6 feet. That's why they have the standard 2M or 5 - 6 ft temperature measurement guidlines.

It's just the opposite during the day that it will be warmer at ground level than it is at 2M as the sun is radiating off the ground and you're closer to the source of the heat. I'm sure you know, but for those who don't, it's not the sun's rays that are coming down and heating the air. It's the sun's rays coming down that heat the ground/surface of the earth and radiates back up and heats us from there. That's why (mostly during daylight hours) it's colder on mountain tops (farther from the heat source) than it is at low elevations (closer to the heat source). Some wonder why it's not warmer at the top of a mountain seeing that it's closer to the sun. That's the reason...
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Quoting originalLT:
TT what I think the GFS missed was that it didn't pick up on the influence the upper level feature(the one moving up from AK, northeast to now western and central NYS) would have on the developement of the SE low that was supposed to move up near the Benchmark. I believe it took energy away from the SE system, kind of strung it out, made it more linear in shape, and caused it not to develope well. Its hard for me to explain, but if one could look at a 24 hour radar loop of the US, you would see what I mean. I'm not as technically versed as you guys!


Yeah that's possible. The entire thing shifted northwest and developed later than expected compared to a handful of days ago. Gave a nice hit to northern New England though.
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A 2" -5" snow would be beautiful to top off the current mess! But I think we're out of the running for anything accumulating here the next two days.
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Well said P451. I'm just hoping for a blended solution between the inland runner, and the out to sea passage.--Like the Benchmark area!
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Quoting TheRasberryPatch:
what will I be looking for Blizz? and just one eye? hmmmmmmmm are we getting the $100? hahahaha the nws has 41F and rain for that time

i have one for you....when i got home last night just before 2am the temp on my weather station (@ 11 feet above ground) was reading 37F. The water on my driveway had already started to freeze and made it like a skating rink with slushy areas. I am guessing the temp at ground level was lower and the winds were helping the water to freeze. I was surprised with temp that high at my station

I had the same thing happen this morning I noticed. It was 35F when I woke up, but everything at the surface had frozen over. Also I do not know if you can tell, but Blue Mountain is covered in ice this morning at the top. It looks really neat. For Monday night, if temperatures fall cool enough I cannot rule out a 2-5in snow for central Pennsylvania. People are always looking too far in advance and then miss out tracking 'surprise' systems. Some winters a 2-5in snow would be a huge deal.
Member Since: December 14, 2007 Posts: 278 Comments: 15045

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About Blizzard92

Cornell University- Atmospheric Sciences Student; Central PA SKYWARN Storm Spotter; American Meteorological Society Member; PA CoCoRaHS Branch Member

Personal Weather Stations

Linglestown, PA
Elevation: 520 ft
Temperature: 24.2 °F
Dew Point: 15.2 °F
Humidity: 68%
Wind: Calm
Wind Gust: 9.0 mph
Updated: 10:37 AM EST on January 18, 2014

About Personal Weather Stations