When the NWS has "NO CLUE" on the coming Artic air

[cctxhurricanewatcher]

LOL!!!!

NWS Corpus see something and NWS Houston thinks we'll be warmer . Geesh, get on the same page.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
251 PM CST THU JAN 13 2005



LONG-TERM (SATURDAY THROUGH THURSDAY)...EXPECT COLDER AIR TO
GRADUALLY FILTER INTO THE CWFA DRG THE PERIOD...AS A SERIES OF UPPER
DISTURBANCES MOVE ACRS THE PLAINS. ISENTROPIC LIFT WL CONTRIBUTE TO
INCREASING CLOUDS BY LATE SUNDAY. GFS PROGS CONDENSATION PRESSURE
DEFICITS TO FALL SUFFICIENTLY FOR STRATIFORM PCPN MONDAY THROUGH
WEDNESDAY...WITH THE BEST CHANCE TUESDAY AS BOTH THE GFS AND NOGAPS
PROGS UPPER DYNAMICS TO MOVE ACRS THE CWFA. WL FCST TEMPS ABOVE
FREEZING DRG THE PERIOD OF PCPN...YET CLOSE TO FREEZING OVR PORTIONS
OF THE NORTH. ALTHOUGH WET BULB TEMPS ALOFT MAY FALL BELOW
FREEZING...SOME FROZEN PCPN COULD REACH THE SURFACE OVR THE NRN
SECTIONS EARLY TUESDAY. HWR...WL NOT MENTION FREEZING/FROZEN PCPN AT
THIS TIME OWING TO UNCERTAINTY. MARINE...SCA CONDITIONS EXPECTED
OFFSHORE BY MONDAY IN RESPONSE TO A SURGE OF COOLER AIR.

[vbhoutex]

I am not one to bash the NWS officies-any one here can tell you that who has been here at S2K any length of time. In fact I get downright mad about it when I see it.

However, reading the different AFD's from around the state is somewhat comical today!! Obviously, none of them are talking to each other which I do not understand. CC seems to have the best handle on it to me and they did the last time if I remember correctly.

[cctxhurricanewatcher]

If you are talking about the Christmas outbreak, they were pretty good on the temps, but very cautious on the precip which was understandable as no one, even those like Bastardi and some here saw the potential,but didn't expect the 6 -12 foot snow.

They must have someone there that's new because in years past on cold they have had to backtrack big time just like some of the NWS offices will be doing soon.

[Burn1]

I am not really refering to anything North of Texas.....In my opinion I just don't see this extreme arctic air filtrating much further south than central plains

[vbhoutex]

I am not really refering to anything North of Texas.....In my opinion I just don't see this extreme arctic air filtrating much further south than central plains

We aren't talking about anything north of Texas either!! Like I said in another post, let's all check back in ten days and we'll see who is right. One question-what do you describe as extreme arctic air in Texas?

[Burn1]

15 to 20 degrees ++ below normal.....Someone had been posting lows in the teens and highs in upper 20's to low 30's??? and not N. TX

[vbhoutex]

15 to 20 degrees ++ below normal.....Someone had been posting lows in the teens and highs in upper 20's to low 30's??? and not N. TX

20º below normal for Houston today for a high would be 41º and a low of 21º if I remember the normal temps I saw on the weathercast at noon. Not sure we will make it to those parameters(lower) with this outbreak, but it could be close. I don't see making the 41º highs tops a problem for at least a few days early next week. We will see.

[CaptinCrunch]

15 to 20 degrees ++ below normal.....Someone had been posting lows in the teens and highs in upper 20's to low 30's??? and not N. TX

D/FW Area!!

M.L.King Day: Partly cloudy, with a high near 34. Northeast wind between 10 and 20 mph.

Monday Night: Partly cloudy, with a low around 25. North northeast wind 5 to 15 mph becoming east southeast.

[Air Force Met]

15 to 20 degrees ++ below normal.....Someone had been posting lows in the teens and highs in upper 20's to low 30's??? and not N. TX

Now it's the central plains? I thought you said it was staying in the northern plains and that most of the US was going to be a tad below normal for a day or two and then above normal? Now the extreme arctic air is going all the way to the central plains?

Yes...I did say that about SE TExas...but a couple of days ago I modified this because of the cloud cover that will be there early next week when the cold air is here...so it won't be as cold because of radiational cooling. However...I think the ideas that the arctic air is coming south and will put most of the central US in the well below normal category for most of the next 4-6 days will trump the idea that only the northern plains would get cold and that most of the rest of the US would see near normal temps (or a tad below) for a day or two and then a warmup.

Given the two overall ideas on the arctic airmass...I will stick with my projection...as it is working out quit well. Yes...I think I will be mistaken about brutally cold air in SE TX...but I think that will be because of the reasons I have outlined in this and other subsequent posts (the cloud cover and the fact the arctic air is coming down in pieces rather than one chunk).

FOr verification of the arctic air coming down into the central plains (vs them only being a tad below normal)...Omaha is forecasting a low of -7 tonight and a high of 3 tomorrow. Given that their avgs are 32 and 12...then that means they are 24F below normal.

Dodge City has a normal of 41 and 18. By Saturday they are calling for 13 and 5....or 20 degrees below normal.

Ok City is calling for temps to be below freezing through Monday. They avg 46 and 26...they are also calling for temps of 20 degrees below normal.

So...the overall idea that the arctic air would go south and put the central and southern plains well below normal was a very good one. We will still wait and see what happens when the bulk of the air slides south. If you have read the forecast discussions...you can see that even the NWS is hedging their bets now and a little worried about busting their forecasts because of the arctic air.

You can also see that those maps you have been using for the last few days that have been calling for above normal temps in the central plains are full of garbage.

[aggiecutter]

All you've got to do is follow the isobars on this loop, and it will tell you which way the cold air is heading. BTW, this is just the tip of the ice-burg so to speak. There is a lot colder air in Alaska starting to move its way south.

Isobar loop...

http://www.weatherunderground.com/US/Re ... ronts.html

Current temp loop...

http://www.weatherunderground.com/US/Re ... ature.html

[Air Force Met]

All you've got to do is follow the isobars on this loop, and it will tell you which way the cold air is heading. BTW, this is just the tip of the ice-burg so to speak. There is a lot colder air in Alaska starting to move its way south.

Isobar loop...

http://www.weatherunderground.com/US/Re ... ronts.html

Current temp loop...

http://www.weatherunderground.com/US/Re ... ature.html

Classic arctic front. Notice how the arctic front is banked up against the rockies in the form of a stationary front.

Classic.

[sertorius]

You can also see this on the satelite imag. the cold air is heading due south-I am currently at 12 here in lawrence and without any cloud cover, I might get below 0 this evening. I'm not sure about after Saturday yet-Man the gfs in the long range is just nuts-it is totally different on the 18z than the 12z today-I have no idea how mets deal with that and try to make a forcast-I have not seen the euro as of yet, but I'd bet it is still progging us to warm up by Tuesday/Wednesday next week. This is the coldest air we have seen for a while-I really wonder how long it will take it to get out of here?? It will become pretty entrenched in the Northern Plains I'd imagine esp. with the snow pack-that temp. difference could play havoc with the models!!! had to check the euro-it is trending colder for this area next week-no longer does it have the chinok winds hollowing as it did 2 days ago-Man, I'd hate to be a met trying to make a forcast that people depended on-what a tough tough time for them!!!

[aggiecutter]

The long range GFS Ensembles puts the central, southern plains and the east in a cold, stormy pattern. There is also strong support from the CFS--The CFS is a coupled ocean-atmosphere model--as it has the mean trough position for February centered over GL-NE with a negative tilt into the central and southern plains.

longrange GFS Enesembles...

http://wwwt.emc.ncep.noaa.gov/gmb/ens/t ... 11312.html

[Kennethb]

Generally, Alaska needs to be "warm" for expansive cold, especially down south. Anchorage is still at 4 degrees, though a warm up is still being forecast. I woud like to see Anchorage and Alaska in general warm before I can feel certain about any significant cold in the south.

[sertorius]

Aggiecutter:

Those sure look better that what I thought was going to happen-I really figured we were going to go to a more zonal pattern, but that looks pretty good-I could def. see some snow at times from that set up. Time well tell, but at least it gives some hope!!! I am going to track the progress of the cold air-you can see the migration pretty well on satelite images to.

[CaptinCrunch]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
214 PM CST FRI JAN 14 2005

.DISCUSSION...
LITTLE CHANGE IN THE OVERALL FORECAST FOR THE NEXT SEVEN DAYS AS DRY
NORTHWEST FLOW ALOFT CONTINUES AND MODIFIED ARCTIC AIR MASS TO THE
NORTH SLOWLY INTRUDES INTO NORTH TEXAS.

STRONG BAROCLINIC ZONE ACROSS OKLAHOMA WITH TEMPERATURES IN THE
TEENS AND 20S ACROSS NORTHERN OKLAHOMA AT 19Z. THIS AIR MASS
(SHALLOW BUT DENSE AND COLD) IS EXPECTED TO SLOWLY SLIDE SOUTHWARD
WITH THE LEADING EDGE CROSSING INTO THE NORTHERN AREAS SATURDAY
EVENING... AND LINGERING INTO TUESDAY BEFORE MOVING OUT OF THE
REGION. THE COLDEST PORTION OF THE ARCTIC AIR WILL STAY NORTH AND
NORTHEAST OF OUR CWA OVER THE NEXT WEEK.

HAVE ADJUSTED LOWS/HIGHS MOST OF THE CWA SUNDAY THROUGH TUESDAY.
AFTERWARDS...THE EASTERN PACIFIC RIDGE MOVES EAST AND BUILDS OVER
THE WESTERN STATES AS THE NOAM VORTEX AND LONGWAVE TROUGH
REPOSITIONS FURTHER EAST - OVER EASTERN CANADA AND ALONG THE EASTERN
SEABOARD...THUS A WARMING TREND FOR FORECAST FOR NTX WED-FRI.

A COUPLE OF PROBLEMS FOR NTX ARE: 1) DEVELOPMENT OF STRATUS ABOVE
THE COLD AIR SUNDAY AND MONDAY... AND 2) LOWS/HIGHS SUN-MON.

CURRENTLY...WE DO NOT THINK SIGNIFICANT WIDESPREAD STRATUS DECK WILL
ADVECT (FORM) NORTH OF I-20 SUNDAY OR MONDAY. AS FOR (2)...
LOW-LEVEL THICKNESS VALUES JUSTIFY MID TO UPPER 20S LOW TEMPERATURES
FOR NORTHERN HALF OF THE AREA... AND SLIGHTLY BELOW GUIDANCE FOR
HIGHS SUNDAY THRU TUESDAY.