Arctic Outbreak delay?

[CaptinCrunch]

I still do not see where you are coming up with this huge blast of cold
air for SE Texas....

May see a day or two next week of just below normal temps, but then
normal temps for the remainder of the month.....

This message is just verifying that any of the colder than normal stuff
will be shifting the east to northeast

OK I don't think you are a troll...so let's talk meteorology. First of all...just below normal would mean that people may only see 5 degrees below normal. So Houston will only see a min of 35 or so and a max of 55 for a day or two. Just below normal means that Wichita KS...which has a normal high of about 40 and a low of 20...will see a low of 15 or so and a high about 35.

Is that what you are saying?

Second of all...given this is siberian air...with temps now -53 in Alaska...and a 1055mb high progged to be coming down into the southern plains of Canada (by all the models)...please give me the 1) Upper air pattern that would be needed to bring this down and 2) provide some analogs of prior arctic airmasses that did not come down into the plains with the current synoptic pattern...but got moved east. I am not talking what you think is going to happen now...but tell me...meteorologically...what is the pattern necessary for an arctic airmass (such as the one currently in AK and stretching into Siberia) to make it into the southern plains. PLease exaplin what the sfc pressures need to be (over 1060?) ...where does the ridge need to be...what about the polar vortex...etc. Since you think the mets here are mistaken on the arctic air take (and the mets in KS which are calling for temps of 25 degrees below normal for several days (which is not just below normal for a day or two)...give a detailed synoptic discussion of what must happen at the sfc and upper levels (across the hemisphere) in order for this to occur. What has to happen to make that arctic air come south?

I'll bite

1.) Upper air pattern? Since the upper air patterns are usually from a west to east flow you would want a more northwest to southeast flow aloft.

2.) I can't really think of any good analogs that would prove other wise.

3.) what is the pattern necessary for an arctic airmass (such as the one currently in AK and stretching into Siberia) to make it into the southern plains? You need a strong high preasure system to form or move in to the Barrin St. this will setup a strong ridge off the Pacific NW hopefully over western AK. that will punch up into Siberia and causing the PJ to go to a north to south flow combined with the PJ. sfc preasure's of 1080 or greater will be idel to substain the artic front. The PV needs to be over or south of the North Pole or Siberia.

The snow and ice pack will also help with the polor air by keeping cold sfc preasure's high, the heavy dense cold air will work under the upper level winds by itself.

Well I hope I pass the test.

[Air Force Met]

A couple of additions. First...the polar vortex needs to be off the poles...but north of the US...maybe west of Hudson Bay. The flow does need to be NW to SE...but only enough to get the arctic air moving. IT can actually be zonal over the US. See the analogs of 1983 and Feb 1989 for that evidence. YOu need a lot of cold air (and it is getting much colder now in AK)...and a nice pressure of 1050 or so.

Look at what is happening with the temps in AK. You can see the cold air dammed up against the Alaska range and Wrangell Mts in the Klondike. CLassic arctic air sliding south.

http://weather.unisys.com/surface/sfc_con_temp_na.html

[PurdueWx80]

Bettles, AK takes the cake now with -56F!!!!

[cctxhurricanewatcher]

Is that -50 and less up there?

I think we should start preparing for something big down here soon. Pipe, pets and plants.

[GalvestonDuck]

'scuse my ignorance, but just HOW do people stay warm there in Alaska?

[MGC]

Well according to my sister in Wasilla (near Anchorage) it is a dry cold. She said last time she was visiting me in Miss a couple of winters ago that she felt colder down here. Its the humity......MGC

[BayouVenteux]

'scuse my ignorance, but just HOW do people stay warm there in Alaska?

With much difficulty in some locales. Read this...

http://www.cnn.com/2005/WEATHER/01/11/a ... index.html

[Burn1]

Sorry for the delay in my response.........I trully believed that and in
actuality is was somewhat true as it didn't hit S. Florida.......Frankly
I just picked NC/SC off the top of my head because I felt it wasn't a
S. Florida hit......That is whay I probably didn't remember.....So....
Thank God! SFL was not hit.....I live here and deal with Corporate Insurance and Wind Storm coverage is a mess. I live 2 blocks from the
Ocean and pay 3k a year just in windstorm.....

In any event you guys go ahead with what you think....Again, just a
friendly post on my opinion looking at NWS climactic outlook......

You will probably be right, however I'm leaning the other way.......

[Johnny]

Burn, can you post that climatic outlook from the NWS? Thanks.

[jeff]

Strong upper low along the N CA coast will move rapidly ESE into TX
Wed afternoon. Increasing moisture combined with strong jet dynamics
and good shear will set the stage for strong to severe thunderstorms
along a Pacific front Wednesday night. 40-45kt low level jet below a
100-120kt mid level jet will provide the fuel for damaging winds along
a squall line. Capping increases along and south of I-10 and the best
dynamics are aimed at NE TX and OK so I expected a strong to severe
squall line over our northern counties and a broken line of showers
across our SW counties. Harris County will lie in between (a line of
thunderstorms). I think any supercells and tornado threat will be to
our NE over NE TX and AR.

NOTE: greater instability and CAPE than forecast will result in
expanding the threat southward and an increasing tornado threat once
the capping is broken. (see Severe Weather for TX thread for detailed write up on the severe threat)

Pacific front moves through early Thursday with drier and cooler air,
but not very cold arctic air. Most guidance is now delaying the
penatration of the arctic air until Sunday. Given the 1056+ mb high
over Alaska and the density of this air mass I think it may be hard to
hold it off to the north. However, I will hesitantly bite on the
guidance and delay the cold air until Saturday. It also appears we
will get several shots with each one colder than the one before it,
instead of the mother load dumping onto us at one time. Cool to cold
air should be in place Sunday and then a disturbance heads across the
area with good isentropic lift and rain late Sunday through Tuesday.
Will be watching this period very carefully because if the models are
wrong and more cold air makes it down here we may have P-type issues
early next week. Right now will go with all rain with lows in the mid
to upper 30's and highs in the 40's. This is extremely low confidence
after Friday with lots of bust potential on temp. forecast given the
havoc movements of very cold and shallow arctic air masses.

Jeff L

[cctxhurricanewatcher]

I notice in this afternoon's Texas NWS AFD's (so far as of 2:30) they are really, really cautious on making a call for this weekend which is good compared to past Arctic Fronts (Christmas) where they were really biting at every model run and moving it to our east or modfying the temps.

Maybe some of them are reading this board.

[CaptinCrunch]

Very well said Jeff, I was looking at the possibility of some freezing precip by maybe Monday night Tuesday for the D/FW area, Let's hope so!!

[gboudx]

After reading AFM's post in this thread: http://www.storm2k.org/phpbb2/viewtopic.php?t=55614 , I'm wondering if the local NWS's will be able to provide any sort of forecast on this air mass. Would they have to wait until they actually see the temps in cities up North as the air oozes southward?

[gboudx]

I notice in this afternoon's Texas NWS AFD's (so far as of 2:30) they are really, really cautious on making a call for this weekend which is good compared to past Arctic Fronts (Christmas) where they were really biting at every model run and moving it to our east or modfying the temps.

Maybe some of them are reading this board.

Gotta scratch your head here.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
240 PM CST TUE JAN 11 2005

.DISCUSSION...
COLD FRONT EDGED INTO OUR NORTHWEST ZONES THIS MORNING...BUT IS
RETREATING NORTH AS UPPER TROF APPROACHES PRODUCING SURFACE PRESSURE
FALLS IN THE TX PANHANDLE. FLOW AROUND THE SURFACE LOW INCREASED
SOUTH WINDS AND PUSHED FRONT BACK NORTH. LOOKS LIKE FROPA WEDNESDAY
AFTERNOON/EVENING WITH LOW POPS FOR THE WEST AND CHANCE POPS FOR THE
EAST. A FEW CELLS MAY BECOME SEVERE WEDNESDAY EVENING EASTERN THIRD
OF THE CWA AS SHEAR PATTERNS ARE FAIRLY STRONG...AND EASTERN ZONES
HAVE DEEPER MOISTURE. ARCTIC AIR SEEMS TO STAY NORTH AND EAST AND
THEREFORE OUR TEMPERATURES ARE NOT AS COLD BEHIND THIS FRONT...IT IS
A PACIFIC AIRMASS RATHER THAN CANADIAN.

OUTLOOK SHOWS PROGRESSIVE PATTERN WITH FAIRLY ZONAL FLOW AND WEST TO
EAST MOVING DISTURBANCES WELL TO OUR NORTH. AIR STAYS DRY THROUGH
NEXT MONDAY AS GULF SEEMS TO STAY BLOCKED. GULF MOISTURE RETURNS TO
SOUTH AND WEST TEXAS MONDAY AND TUESDAY...SO IF MODELS ARE HOLDING
DRY AIR IN TOO STRONG THOSE TWO DAYS MAY PRODUCE SHOWERS IN THE
SOUTHERN ZONES.

[BayouVenteux]

After reading AFM's post in this thread: http://www.storm2k.org/phpbb2/viewtopic.php?t=55614 , I'm wondering if the local NWS's will be able to provide any sort of forecast on this air mass. Would they have to wait until they actually see the temps in cities up North as the air oozes southward?

Good point. I recall the mid-January arctic outbreak in 1986 that occured the weekend of the Super Bowl and a few days before the Challenger disaster was not originally predicted to move as far into the south as it eventually (and with tragic consequences for the astronauts) did. My wife and I left our house packed with lightweight clothes based on the weather report which made no mention of any cold air until sometime later in the week. We were in New Orleans on Saturday enjoying temps in the 70's, but that night on the local N.O. news they were doing a 180 apparently based on new information. We awoke on Sunday morning to sleet, freezing rain and temps struggling to pass 30 degrees. Took 5 hours to drive the 75 miles back to Baton Rouge, as ice covered all the elevated highways and bridges.

So yes, despite the fact that the weather service has models and upper air soundings, satellite, etc. at their disposal, when you have a mass of super cold air at the surface, in the right set of circumstances it's going to find a way to throw it's weight southward, and the best they can do is monitor the forward progress and adjust accordingly based on the obs.

[Brent]

Is that -50 and less up there?

Yeah... but that's not unusual up there. Remember, Northern Alaska is in 24 hours of total darkness right now and even in the South, it's only 5-6 hours of daylight.

The good thing is, the Summers aren't hot at all compared to here. I'd love to live there then, also 18-19 hour days in most spots with 24 hours of light over the North(a little much). In the winter though, while I like it cold, that's TOO cold.

Juneau(the Capital)'s winters aren't bad at all though. Snows a TON too(compared to colder areas). Days are the longest there. That'd be a place to live if I ever do up there.

The average in January is 21/31 and in July 49/64

Precip averages 8.20" in October and only 2.96" in April(those are the extremes). Coldest temperature ever is -22.

[cctxhurricanewatcher]

.

Maybe some of them are reading this board. [/quote]

Gotta scratch your head here.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
240 PM CST TUE JAN 11 2005

.DISCUSSION...
COLD FRONT EDGED INTO OUR NORTHWEST ZONES THIS MORNING...BUT IS
RETREATING NORTH AS UPPER TROF APPROACHES PRODUCING SURFACE PRESSURE
FALLS IN THE TX PANHANDLE. FLOW AROUND THE SURFACE LOW INCREASED
SOUTH WINDS AND PUSHED FRONT BACK NORTH. LOOKS LIKE FROPA WEDNESDAY
AFTERNOON/EVENING WITH LOW POPS FOR THE WEST AND CHANCE POPS FOR THE
EAST. A FEW CELLS MAY BECOME SEVERE WEDNESDAY EVENING EASTERN THIRD
OF THE CWA AS SHEAR PATTERNS ARE FAIRLY STRONG...AND EASTERN ZONES
HAVE DEEPER MOISTURE. ARCTIC AIR SEEMS TO STAY NORTH AND EAST AND
THEREFORE OUR TEMPERATURES ARE NOT AS COLD BEHIND THIS FRONT...IT IS
A PACIFIC AIRMASS RATHER THAN CANADIAN.

OUTLOOK SHOWS PROGRESSIVE PATTERN WITH FAIRLY ZONAL FLOW AND WEST TO
EAST MOVING DISTURBANCES WELL TO OUR NORTH. AIR STAYS DRY THROUGH
NEXT MONDAY AS GULF SEEMS TO STAY BLOCKED. GULF MOISTURE RETURNS TO
SOUTH AND WEST TEXAS MONDAY AND TUESDAY...SO IF MODELS ARE HOLDING
DRY AIR IN TOO STRONG THOSE TWO DAYS MAY PRODUCE SHOWERS IN THE
SOUTHERN ZONES.[/quote]



What the ? I take back what I said. What models are they reading up at DFW?

[cctxhurricanewatcher]

I take back what I wrote earlier. NWS San Antonio, Houston and Brownsville act like nothing is coming based on one model run. Be consistent folks.

[Burn1]

Just go to NWS forecasts and look at 6 to 10, along with 8 to 14 day
forecasts.....

Seems like some of these recent posts are verifying some of the things
I have suspected.....

[MGC]

NWS New Oreleans has raised the min temps this weekend considerably from low 20's to mid 30's on the Miss coast. Looks like the bulk of the cold air will move into the Ohio Valley and not the deep south.....MGC