Very Disturbing PRELIM DISC from HPC

[LithiaWx]

Wow.

98 at Dobbins AFB down the street from my house. That is exceeding even the highest model output I saw for this date all week. It is 103 in Rome and 100 in Cartersville. This is an amazing heat wave. The writing appears to be on the wall. I think KATL will tie or exceed the all-time high of 105 by Saturday. The June record of 101 should fall easily. There isn't a cloud in sight outside. No high clouds nothing but clear blue and hellishly hot.

My car thermometer read 102 on well on my way home in Norcross and then crept up to a sickening 111 on I-285 near I-75 in Rush hour traffic. It fell back down to 103 by the time I pulled in my driveway in Marietta. I know car thermometers are not reliable but it was friggin hot out there on the ride home today with all the extra heat from other cars and blacktop.

I'm pulling for records to fall at this point. If it's going to be this hot let there at least be something cool to talk about.

[FoothillsNC]

18z GFS has a few folks in VA, NC, SC getting lucky with thunderstorms developing very late Saturday. In heat waves, if you get a storm, it's a really big one. They have to have strong updrafts to break the cap that will be in place. So far, no one is buying into even a remote chance, but GFS is pretty good at this type of thing and has had this a few runs. As 5H vort rotates deeply down the front side of the ridge (going from eastern Ohio, West VA due south through Carolinas) then something can fire up, even very late Saturday night well past midnight. Talk about being really muggy the next day though

[Hoosier]

Numerous daily/all-time June records fell in the Ohio Valley today.

[snowlover91]

18z GFS has a few folks in VA, NC, SC getting lucky with thunderstorms developing very late Saturday. In heat waves, if you get a storm, it's a really big one. They have to have strong updrafts to break the cap that will be in place. So far, no one is buying into even a remote chance, but GFS is pretty good at this type of thing and has had this a few runs. As 5H vort rotates deeply down the front side of the ridge (going from eastern Ohio, West VA due south through Carolinas) then something can fire up, even very late Saturday night well past midnight. Talk about being really muggy the next day though

I think along I-95 and east there is a good shot at some storms forming all the way down into Southern GA as the GFS and NAM both have a thermal trough developing inland, causing dew point pooling in the eastern areas with dew points well over 80 across all of eastern NC, SC, and parts of GA on Saturday and Sunday. Look at the LI index the GFS is forecasting, pretty extreme if you ask me. I think with the ridge centered further SW of these areas there will be afternoon storms between 3-8pm that fire and continue till midnight or a little after. With LI of -16 and CAPE over 6000 in areas, you know it won't take much. Plus, the GFS, NAM, and Euro are all showing short waves moving through Saturday which should be enough to trigger some nasty storms. I'm looking forward to the prospect of some good summer storms to cool things off.

[CandymanColumbusGA]

Numerous daily/all-time June records fell in the Ohio Valley today.

According to http://coolwx.com/record/ at 7 PM EDT.

As of this picture 75 locations in the US broke a record high. Another 17 are tying their record highs. Many other locations, 33 to be exact, were within 3 degrees of tying their record high for the day too.

Seven, yes 7, locations broke their ALL-TIME record high. That means they saw the warmest temperature ever, for any date, today.

On top of 7 all-time records falling, another 28 saw their highest June temperature in their recorded history.

It is time sensitive, so get a look quickly! Another note, these are unofficial and we'll have to wait until tomorrow to verify.

http://www2.wrbl.com/weather/2012/jun/28/record-highs-falling-across-country-wf-9898/?referer=None&shorturl=http://bit.ly/NHJ8Fl

[dwagner88]

We hit 103 today. NWS forecast, based on model guidance being "overdone" was for 98. Looks like the models were right. I think we will flirt with our all time record of 106 sometime this weekend.

[valkhorn]

We were only forecast to hit the mid 90s. We hit 101 in Knoxville today. It was a very dry heat so it was actuallly pretty tolerable. We had a 16% humidity this aftenoon. It felt like the desert. Something tells me we'll be in the 100-105 range tomorrow.

[FoothillsNC]

We hit 103 today. NWS forecast, based on model guidance being "overdone" was for 98. Looks like the models were right. I think we will flirt with our all time record of 106 sometime this weekend.

We were only forecast to hit the mid 90s. We hit 101 in Knoxville today. It was a very dry heat so it was actuallly pretty tolerable. We had a 16% humidity this aftenoon. It felt like the desert. Something tells me we'll be in the 100-105 range tomorrow.

Its looking like a lot of folks will find this heat surprising. Dewpoints will drop down to ridiculous levels again tomorrow and relative humidity into the teens or 20's (esp. on the east and se sides of the apps). Looks like 105 is doable in places between Athens and GSP region for sure.

[downeastnc]

Its looking like a lot of folks will find this heat surprising. Dewpoints will drop down to ridiculous levels again tomorrow and relative humidity into the teens or 20's (esp. on the east and se sides of the apps). Looks like 105 is doable in places between Athens and GSP region for sure.

Personally for me these type of heat waves are really not that bad, I would rather have it 100-105 with mixed out DP and dry air than upper 90's with DP in the upper 70 low 80 range...those are the day that for me its unbearable to be outside. I bet in some places you see the "feels like" temp a bit lower than the actual temp if the DP/humidity crash low enough.

This location will see heat indexs in the 120-130 range

http://www.weather.g...story/KOCW.html

Its at the Washington NC airport near the river/sound and I have seen this location hit the mid 120's heat index several times.

[FoothillsNC]

I bet in some places you see the "feels like" temp a bit lower than the actual temp if the DP/humidity crash low enough.

And that's exactly what will happen tomorrow in the lee of the Southern Apps. This also happened in 2007 here, very strongly, with dewpoints in the upper 40's. The models under-did the rel. humidity and dewpoints already in Alabama today, and I won't be surprised to see them be a little too high here (already GFS has dewpoints going into upper 50's) so with such strong northwest flow and an already extremely dry airmass and deep downsloping, the models may really be blowing the dewpoints in northeast Ga and western SC by about 10 degrees. Wouldn't surprise me to see some dewpoints actually drop to near 40 near GSP, Toccoa or Anderson tomorrow afternoon around 4 pm.

[downeastnc]

And that's exactly what will happen tomorrow in the lee of the Southern Apps. This also happened in 2007 here, very strongly, with dewpoints in the upper 40's. The models under-did the rel. humidity and dewpoints already in Alabama today, and I won't be surprised to see them be a little too high here (already GFS has dewpoints going into upper 50's) so with such strong northwest flow and an already extremely dry airmass and deep downsloping, the models may really be blowing the dewpoints in northeast Ga and western SC by about 10 degrees. Wouldn't surprise me to see some dewpoints actually drop to near 40 near GSP, Toccoa or Anderson tomorrow afternoon around 4 pm.

LOL so I guess if there is a silver lining to this that is it, so even though its 105 out it will "only" feel like 102.... guess thats not much to get excited over but it is better than 99 with a HI of 115.

[griteater]

Personally for me these type of heat waves are really not that bad, I would rather have it 100-105 with mixed out DP and dry air than upper 90's with DP in the upper 70 low 80 range...those are the day that for me its unbearable to be outside. I bet in some places you see the "feels like" temp a bit lower than the actual temp if the DP/humidity crash low enough.

This location will see heat indexs in the 120-130 range

http://www.weather.g...story/KOCW.html

Its at the Washington NC airport near the river/sound and I have seen this location hit the mid 120's heat index several times.

NAM MOS has Jacksonville, NC Marine Corp Air Station at 103 temp, 78 dewpoint Sat at 2PM

[Stormsfury]

Example of how dry the airmass is. Paducah KY set a record low of 54 on the 27th, rising to 98 that afternoon. Today a record high of 105 was set.

[downeastnc]

NAM MOS has Jacksonville, NC Marine Corp Air Station at 103 temp, 78 dewpoint Sat at 2PM

Hard to do that here in the east, I would think it is pretty rare to get actual air temps that high with DP that high as well....seems like anytime we get 100-105 here the air is usually pretty dry. Of course on the tarmac at the airfield I am sure its absolutely insanely miserable and it could be possible, with a temp of 103 anda DP of 78 the HI would only be 122 lol..... however the link I posted above for Washington is about as bad a offical station as I have seen for extreme heat indexs, that location gets temps and DP together that are pretty bad....I remember back in 2007 they had a 99 temp with a 84 DP that equals a heat index of 128......and that was at 11 am

[snowlover91]

Hard to do that here in the east, I would think it is pretty rare to get actual air temps that high with DP that high as well....seems like anytime we get 100-105 here the air is usually pretty dry. Of course on the tarmac at the airfield I am sure its absolutely insanely miserable and it could be possible, with a temp of 103 anda DP of 78 the HI would only be 122 lol..... however the link I posted above for Washington is about as bad a offical station as I have seen for extreme heat indexs, that location gets temps and DP together that are pretty bad....I remember back in 2007 they had a 99 temp with a 84 DP that equals a heat index of 128......and that was at 11 am

Actually the GFS and NAM show dewpoints in the low 80s east of I-95 due to a thermal trough developing along I-95 as well as the sea breeze pushing inland and "bottling" the moisture so to speak. Most areas from Raleigh west will have low dewpoints in the 50s, low 60s, and even some 40s possible closer to the piedmont. However, if the models are to be believed, once you hit Wilson to Greenville dewpoints will go from 60s and low 70s to 80s in less than 50 miles. It will be humid here in the east, not for most, but for us it will be. Dewpoints will probably mix out some in the afternoon to the 70s but still that is plenty muggy.

[valkhorn]

LOL so I guess if there is a silver lining to this that is it, so even though its 105 out it will "only" feel like 102.... guess thats not much to get excited over but it is better than 99 with a HI of 115.

Having been out in the desert compared to the southeast US, I would MUCH rather take 110F with a 40F dewpoint than 95F with a 75F degree dewpoint. It's actually quite nice and really is a welcome difference from the typical summers you see around here even if it is above 100F.

[downeastnc]

Actually the GFS and NAM show dewpoints in the low 80s east of I-95 due to a thermal trough developing along I-95 as well as the sea breeze pushing inland and "bottling" the moisture so to speak. Most areas from Raleigh west will have low dewpoints in the 50s, low 60s, and even some 40s possible closer to the piedmont. However, if the models are to be believed, once you hit Wilson to Greenville dewpoints will go from 60s and low 70s to 80s in less than 50 miles. It will be humid here in the east, not for most, but for us it will be. Dewpoints will probably mix out some in the afternoon to the 70s but still that is plenty muggy.

I would think if that happens the actual temp wouldnt get much over 100 though.....if we do end up with temps in the low 100's and a DP in the low 80's that would be brutally bad and I bet the model are overdone.....I would think the worse hours will be late morning and the late evening when humidity and DP are still high but during the heat of the day when air temps hit there highest I suspect the DP will fall off quite a bit. IF it doesnt though

[WilkesboroDude]

Hot wind blowing across the North Carolina mountains early this morning.

Some spots are 10-20 degrees warmer than places like Raleigh.

[NavarreDon]

Amazing temp diff. in the Mnts. this am. I was at 60° @ 6:00 am. The airport 21 miles away was @ 76°. Here is what GSP had to say about it but there is not alot of elev. diff between Weaverville & Fletcher.

THE EARLY

MORNING READINGS ARE SHOWING JUST HOW UNUSUAL THIS AIR MASS IS. SOME

MTN TOP LOCATIONS ARE ABOVE THE LOW LEVEL INVERSION WITH TEMPS IN

THE 70S TO LOW 80S AND WINDY CONDITIONS.

Here is part of the obs chart from KAVL for last night & this morning. A 9° temp rise from 1:00 am to 2:00 am. A 6 hour obs window max temp of 95°! A question....Will 95° count as the daily high or do the hourly obs only count as official temps?

D

a

t

e Time

(edt) Wind

(mph) Vis.

(mi.) Weather Sky Cond. Temperature (ºF) Relative

Humidity Wind

Chill

(°F) Heat

Index

(°F) Pressure Precipitation (in.) Air Dwpt 6 hour altimeter

(in) sea level

(mb) 1 hr 3 hr 6 hr Max. Min. 29 05:54 N 6 10.00 Fair CLR 76 51 42% NA 78 30.03 1013.4 29 04:54 NE 6 10.00 Fair CLR 75 52 45% NA NA 30.03 1013.3 29 03:54 N 9 10.00 Fair CLR 77 50 39% NA 78 30.02 1013.0 29 02:54 Calm 10.00 Fair CLR 78 51 39% NA 79 30.03 1013.3 29 01:54 Vrbl 5 10.00 Fair CLR 77 52 86 67 42% NA 78 30.03 1013.6 29 00:54 S 3 10.00 Fair CLR 68 61 78% NA NA 30.04 1014.1 28 23:54 N 7 10.00 Fair CLR 76 54 47% NA 78 30.04 NA 28 22:54 Calm 10.00 Fair CLR 73 59 62% NA NA 30.05 1014.7 28 21:54 NW 7 10.00 Fair CLR 76 57 52% NA 78 30.04 1014.6 28 20:54 N 7 10.00 Fair CLR 80 60 51% NA 81 30.04 1014.7 28 19:54 Calm 10.00 Fair CLR 85 65 95 85 51% NA 87 30.04 1014.7 28 18:54 S 8 10.00 Fair CLR 88 64 45% NA 89 30.04 1014.8 28 17:54 Vrbl 7 10.00 Fair CLR 91 60 35% NA 90 30.05 1014.8 28 16:54 S 6 10.00 Fair CLR 92 57 31% NA 91 30.06 1015.0 28 15:54 S 9 10.00 Fair CLR 92 55 29% NA 90 30.07 1015.4

[Isopycnic]

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE WILMINGTON NC

632 AM EDT FRI JUN 29 2012

.NEAR TERM /THROUGH TONIGHT/...

AS OF 630 AM FRIDAY...NO SIGNIFICANT CHANGES NEEDED AS 06Z MODELS

DID NOT CHANGE APPRECIABLY FROM THE 00Z RUN. IT IS FASCINATING

WATCHING THE HOT AIRMASS CROSS THE MOUNTAINS OF VIRGINIA AND NORTH

CAROLINA THIS MORNING. EVEN BEFORE SUNRISE SURFACE AIR TEMPERATURES

AT THE RIDGETOPS AND IN THE DOWNSLOPE MIXING ZONE ARE IN THE MID TO

UPPER 80S...EXTENDING FROM ROANOKE AND GALAX VA THROUGH MOUNT AIRY

INTO NORTH WILKESBORO NC.

NATIONAL WEATHER SERVICE WAKEFIELD VA

600 AM EDT FRI JUN 29 2012

ROANOKE CLEAR 85 (at 6am? lol)

BLACKSBURG CLEAR 81

ABINGDON* N/A 65

NORTH CAROLINA WEATHER ROUNDUP

NATIONAL WEATHER SERVICE RALEIGH NC

600 AM EDT FRI JUN 29 2012

MOUNT AIRY CLEAR 86

JEFFERSON CLEAR 81

ASHEVILLE MOCLDY 76

WINSTON-SALEM CLEAR 73

RALEIGH-DURHAM CLEAR 71

CHAPEL HILL CLEAR 70

CHARLOTTE CLEAR 68

NEW BERN CLEAR 73

[Isopycnic]

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE BLACKSBURG VA

337 AM EDT FRI JUN 29 2012

TO PUT INTO CONTEXT HOW IMPRESSIVE THIS WARMTH IS...IF ROANOKE

REACHES OR EXCEEDS 100 TODAY...IT WILL BE THE FIRST TIME THIS HAS

HAPPENED IN JUNE SINCE 1959. IN 100 YEARS OF RECORDS AT ROANOKE...A

100 DEGREE DAY IN JUNE HAS ONLY BEEN DOCUMENTED 13 TIMES (TWICE IN

JUNE IN 1930, 1931, 1934 AND 1936)

KFCX VAD WIND PROFILE SHOWS 35-40KT WINDS 2K FT OFF THE SFC WHICH

HAS GENERATED SOME IMPRESSIVE WIND GUSTS AT THE HIGHER ELEVATION

SITES. THE LOCAL WRF MODEL HAS CAPTURED THIS WELL...AND SHOWS THESE

WIND WEAKENING IN THE AFTERNOON. THESE GUSTY WINDS AND DEW POINTS

IN THE MID-UPPER 60S WILL GENERATE RH VALUES AS LOW AS 25-30 PERCENT

IN SOME AREAS.

[FoothillsNC]

Hot wind blowing across the North Carolina mountains early this morning.

Some spots are 10-20 degrees warmer than places like Raleigh.

and this is indicative of the hot air aloft. RUC now captures this, so the ECMWF was about right a few days ago in showing +30 in some pockets. Just unbelievable. My county finally got added to the heat advisory a while ago, but some western Upstate Counties and northeast Georgia counties still aren't, and this is where there is going to be extreme downsloping and the hottest 850's of the last 125 years are being shown.

Some all time records are probably coming to part of TN/NC/SC/GA today.

[Lookout]

and this is indicative of the hot air aloft. RUC now captures this, so the ECMWF was about right a few days ago in showing +30 in some pockets. Just unbelievable. My county finally got added to the heat advisory a while ago, but some western Upstate Counties and northeast Georgia counties still aren't, and this is where there is going to be extreme downsloping and the hottest 850's of the last 125 years are being shown.

Some all time records are probably coming to part of TN/NC/SC/GA today.

Well one reason for FFC's lack of advisories is their low temp and heat index criteria. I personally think it's stupid when dealing with highs of 105 or greater and it also looks stupid when you see so many advisories everywhere but here but that's their criteria.

Those mountain temps btw are absolutely UNREAL. Thanks to those who posted about it. RUC actually has 850mb temps closing in as high as 31c in that pocket per soundings (as high as 30.4/30.5c within that pocket) And you'll notice I'm firmly under those 30c 850mb temps

I'm hoping atlanta gets to reach 30c because I know Larry will flip out LOL

[eyewall]

I believe the all time record for Fayetteville, NC is 110. I doubt that will happen though.

[FoothillsNC]

Well one reason for FFC's lack of advisories is their low temp and heat index criteria. I personally think it's stupid when dealing with highs of 105 or greater and it also looks stupid when you see so many advisories everywhere but here but that's their criteria.

RUC actually has 850mb temps closing in as high as 31c in that pocket per soundings (as high as 30.4/30.5c within that pocket) And you'll notice I'm firmly under those 30c 850mb temps

I'm hoping atlanta gets to reach 30c because I know Larry will flip out LOL

If you loop any model at 850 and 5h, you'll see how the hot air rolls down the ridge in the Southern Apps, going from Tenn due south to SC and GA this afternoon. Combined with downslope this will maximize all the heating phenomenon known in meteorology, that's why I'm thinking this will be a truely historic hot day and some all time records are coming. So with that technical reasoning on why or why not some offices don't issue a heat advisory, I think the places that experience a "heat burst" phenomenon today are directly around upstate SC to your area, roughly ATL GSP CLT zone. This looks about like August 2007, but maybe warmer (unless a much wetter ground this time affects it). I remember vividly standing outside at midnight back then facing my northwest woods, and 93 degree heat and strong winds blasting me in the face..it felt unbelievable and that memory is definitely etched in my mind because I'd never felt anything like it at midnight. I'm not sure how widespread those winds were, but I think that could be what's in store today, with dewpoints probably dropping below any of the models forecast, along with relative humidity in the teens. Going to be interesting.

I just noticed RUC has 115 degrees at the surface at 5 pm around just south of Athens toward Augusta.

[HurricaneTracker]

With Asheville starting the day at 76*, and looking out the window reveals clear skies - we might be 90 by mid-morning. Certainly seems 98 is doable. Question now is will we tie or break the all-time high of 100 set in Aug 1983?

It is going to be very close. If we can realize the true mixing depth (and that seems to be well underway this morning with winds mixing out the inversion layer), then 100 might very well happen.

My unofficial forecast for KAVL is 98, tying the record.

[Lookout]

If you loop any model at 850 and 5h, you'll see how the hot air rolls down the ridge in the Southern Apps, going from Tenn due south to SC and GA this afternoon. Combined with downslope this will maximize all the heating phenomenon known in meteorology, that's why I'm thinking this will be a truely historic hot day and some all time records are coming. So with that technical reasoning on why or why not some offices don't issue a heat advisory, I think the places that experience a "heat burst" phenomenon today are directly around upstate SC to your area, roughly ATL GSP CLT zone. This looks about like August 2007, but maybe warmer (unless a much wetter ground this time affects it). I remember vividly standing outside at midnight back then facing my northwest woods, and 93 degree heat and strong winds blasting me in the face..it felt unbelievable and that memory is definitely etched in my mind because I'd never felt anything like it at midnight. I'm not sure how widespread those winds were, but I think that could be what's in store today, with dewpoints probably dropping below any of the models forecast, along with relative humidity in the teens. Going to be interesting.

I just noticed RUC has 115 degrees at the surface at 5 pm around just south of Athens toward Augusta.

If it gets that hot, someone shoot me lol.

Plus, Both the nam and gfs show temps around 108 from near athens to central NC the next few days. The nam is even showing lows in the mid freaking 80s. I find it hard to believe, with this much model agreement, that all time record highs won't be set, as you said. Plus the latest rap is showing temps above 90 degrees still at 1am from athens to around Monroe, NC/Rockingham Which likely means lows in the 80s, which is *extremely* rare where I am. Even back in 2007 when it reached around 105 to 107 here or so here iirc, low temps still got down to 75 to 77. So that would be extraordinary to say the least.

Btw, the soil moisture where I'm at is not high at all. Other than getting lucky once or twice and getting a little rain, the ground is already dry here. Other than those 2 times or so, which was a while back, my surrounding area, especially me of course, just hasn't had much.

Current rough soil moisture here.

Current soil moisture anomalies.

Either way, all that will do I think is increase dps/HI's making it worse. Even if the RUC/RAP is overdone, the nam/gfs shows temps close to 110 in the corridor I mentioned. Historical heat to say the least.

This is just a *sick* image. I mean seriously???

[nchighcountrywx]

Hot winds are raking the ridgelines of the NC Mountains of Avery County this morning

Grandfather Mountain at 8:56am

Winds NW at 38mph gusting to 49mph

Max 1 Hour Wind: 57mph

Temperature: 67.7

Relative Humidity 53% (dropped to about 28% Thursday during the afternoon)

Image Courtesy of Appalachian State University AppalAir Project

[griteater]

Virginia and DC area is actually leading the way this morning with a few 90-91 deg readings showing up on MesoWest.

[Wow]

There's a plume of high cirrus clouds this morning stretching across the SW quadrant of NC. Actually taking out the sun right now.