Texas Fall-2015

[TeamPlayersBlue]

Example of zonal -EPO blast from the CMC. 500mb heights are high thinking zonal flow is warm but look at the surface, the freeze line is coming from Oklahoma. Models just thinks the upper flow blasts everything east but in reality and the surface HP shoves it due south.






This if it were to occur would be an Arctic outbreak TG through that weekend

I agree with you completely, but last year, didnt we have a few times where the HP wouldnt come all the way down? What was keeping it from crashing into us?

[Ntxw]

I agree with you completely, but last year, didnt we have a few times where the HP wouldnt come all the way down? What was keeping it from crashing into us?

The PNA was too positive then. I recall it a few times. +PNA slid the HP to our north and east and hammered New England.

This weekend's cold air mass (40s for high's) is a result of height rises in the GOA not yet a full -EPO block. Next week though it will be, just question I believe how cold is the air mass.

[TeamPlayersBlue]

So PNA is more of a Block off the coast of Cali, EPO more in the GOA? I no roughly where the measurements occur but not on the top of my head.

So i just looked at the GFS run. Holy moly, so. Were in mostly la la land but the first big possible block occurs next week Tuesday. Alot of that cold air becomes modified over the Pac NW though it seems. But at 384, 1059 HP crossing the border lol. Really sees something big. The Typhoon in the Pacific seemed to have an effect on the high for the second half of the run. Comes into play around 264 hrs. Seriously going to save this run though. MacFarland signature at its finest? PV West Hudson Bay, strong -EPO, undercutting low.....

Man have i missed you winter.

Edit: Also, im pretty sure the HP at 264 will be MUCH stronger than what the GFS is saying with that kind of Upper Level setup.


Last big high is SIBERIAN EXPRESS. Lol. I love it.

[Ntxw]

So PNA is more of a Block off the coast of Cali, EPO more in the GOA? I no roughly where the measurements occur but not on the top of my head.

We know the -EPO is ridge into Alaska/GOA. PNA has been misunderstood for some years, we always associated it with being good for Texas. But in reality -PNA causes more weather here than does the +PNA. A -PNA digs troughs into the west and bleeds into the plains. This is when you see the big cutoff lows near 4 corners or SW US and cold air is pouring into it. +PNA is the opposite ridge into the 4 corners, this is great for folks east of the Mississippi. For us most of the time it is dry NW flow and back door cold fronts. There are slight variations. McFarland's paper states specifically that for major cross polar flow attacks into the RGV the necessary ingredients is -EPO/-PNA. In short PNA is more ridge/trough position in the western US

Snippets from his paper

"As shown in Figure 4, the 500 mb patterns during the 1951 and 1962 Arctic outbreaks were very similar; a deep polar vortex over Baffin Bay, a major trough over the northern United States with an east-west trough line, zonal flow south of the trough line and northerly flow from a high amplitude ridge north of the trough line. The events preceding these patterns were also very similar."

"Several 500 mb synoptic features are common to all major Arctic outbreaks described. The long wave pattern includes a high amplitude ridge over western North America or the eastern Pacific with a deep 500 mb long wave low system centered between Hudson Bay and Greenland. When this long wave pattern exists, the conditions for formation of the Arctic air mass and the potential for its southward movement are favorable.'

[weatherdude1108]

EWX mentions absorption of a Pacific tropical system into the Nino subtropical flow next week. I think that was already talked about on this forum earlier. Anyway. Nice and chilly.

000
FXUS64 KEWX 172055
AFDEWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
255 PM CST TUE NOV 17 2015

.SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...COLD FRONT IS WELL
SOUTH AND EAST OF THE CWA. ELEVATED INSTABILITY AND FORCING HAS
LED TO THE DEVELOPMENT OF ISOLATED SHOWERS BEHIND THE FRONT ACROSS
THE EASTERN HILL COUNTRY AND CENTRAL TEXAS...AND NOW BACK JUST
WEST OF SAN ANTONIO. THE ELEVATED SHOWERS SHOULD REMAIN ISOLATED
AND CONTINUE NORTHEAST THROUGH THE REMAINDER OF THE AFTERNOON.
CLEARING LINE HAS BEEN SLOWER TO PROGRESS EAST...AND WAS
APPROACHING THE I-35 CORRIDOR MID AFTERNOON. CLEARING WILL
EVENTUALLY TAKE PLACE ACROSS THE EASTERN CWA LATER THIS EVENING
EVENING.

LOCALIZED ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS HAVE
ALSO DEVELOPED ACROSS THE FAR WESTERN HILL COUNTRY AND RIO GRANDE.
FUEL MOISTURE REMAINS ABOVE NORMAL AND WINDS SHOULD SUBSIDE
QUICKLY THIS EVENING...SO WILL NOT BE ISSUING RED FLAG AT THIS
TIME.

WINDS ACROSS THE HILL COUNTRY AND RIO GRANDE SHOULD SUBSIDE AFTER
SUNSET. DRIER AIRMASS IN PLACE AND CLEARING SKIES WILL LEAD TO
LOWS ON WEDNESDAY AND THURSDAY MORNINGS IN THE LOW TO MID 40S...
WITH EVEN SOME LOCATIONS IN SHELTERED...DRAINAGE AREAS OF THE
HILL COUNTRY IN THE MID TO UPPER 30S. SOME PATCHY FROST COULD BE
POSSIBLE ACROSS PORTIONS OF THE HILL COUNTRY. HIGHS WEDNESDAY
REBOUND INTO THE LOW TO MID 70S UNDER FULL SUN.

&&

.LONG TERM (THURSDAY THROUGH TUESDAY)...DRY CONDITIONS CONTINUE
INTO THURSDAY. RETURN FLOW SETS UP FRIDAY WITH GRADUALLY
MODIFYING LOW LEVELS.

MODELS ARE IN GOOD AGREEMENT THAT A COLD FRONT WILL MOVE THROUGH
THE CWA SATURDAY MORNING...WITH LOW RAIN CHANCES PRIMARILY ACROSS
THE SOUTH WHERE DEEPER MOISTURE RESIDES. BREEZY AND COOLER
SATURDAY WITH HIGHS ONLY IN THE UPPER 50S TO LOW 60S.

EARLY NEXT WEEK THE GFS AND ECMWF DIVERGE. GFS DEVELOPS WEAK
ISENTROPIC UPGLIDE PATTERN AND LOW CHANCES FOR RAIN ACROSS THE
SOUTH SUNDAY AND SUNDAY NIGHT WITH CLOUDY AND COOL CONDITIONS
ACROSS THE ENTIRE CWA. ECMWF IS MUCH DRIER BUT COOL. HIGHS SUNDAY
LIKELY WILL NOT MAKE IT OUT OF THE 50S. GFS IS HINTING THAT
REMNANT MOISTURE/ENERGY FROM A POTENTIAL TROPICAL SYSTEM IN THE
PACIFIC BEING ABSORBED INTO THE SUB-TROPICAL FLOW ALOFT AND MOVING
INTO SOUTH-CENTRAL TEXAS LATE MONDAY THROUGH TUESDAY. THE ECMWF
IS DELAYED WITH THE ISENTROPIC UPGLIDE...NOT DEVELOPING UNTIL
TUESDAY AND THE POTENTIAL PACIFIC CONNECTION NOT ARRIVING UNTIL
WEDNESDAY OF NEXT WEEK. FOR NOW WILL KEEP COOL CONDITIONS MONDAY
INTO TUESDAY...WITH LOW POPS DUE TO UNCERTAINTY.

[Ntxw]

FW put up a graphic on annual rainfall



Also currently it is snowing in Amarillo, and will in Pampa later this evening. There was a tornado there 24 hours ago which preliminary surveys have EF3 from the NWS.

[Ntxw]

For fun, 18z GFS has the same ridge into the GOA and builds it up into Alaska and the Arctic and shoves down a near 1058mb HP the following weekend (la la land) and to ring in December. Maybe we get a late Nov/early Dec 2013 redux?

[TeamPlayersBlue]

18z pretty much has the same ideas as the 12z

[Ntxw]

The signal is quite strong

[Ralph's Weather]

06Z op GFS looks odd with the trough way off of the West Coast. The ensembles look more in line with current thinking and most individuals show snow sometime after TDay.
Also, as I mentioned in my forecast I put out yesterday for my area there is an very outside chance of some flurries on Sunday.

[srainhoutx]

Morning briefing from Jeff:

Active storm track to continue across the southern plains into December with increasingly colder air masses.

Dry and cool air mass in place this morning a big contrast to yesterday morning with current dewpoints running some 20-30 degrees lower. Upper level storm system responsible for the active weather on Tuesday is moving NW out of the central plains with modified Canadian air mass advecting southward over the recent snowfall over the western high plains and eastern Rockies. This will result in clear and cool weather for SE TX today-Friday with lows in the 40’s/50’s and highs in the 60’s/70’s.

Stronger cold front will plunge down the plains on Friday and arrive into SE TX Saturday. Moisture begins to increase Friday afternoon and expect an increase in cloud cover and likely a few showers with the frontal passage early Saturday. Air mass behind this front is cold and high temperatures will be prior to the front on Saturday with falling temperatures in the afternoon into the 50’s. Cold air advection continues into Sunday with lows falling well into the 40’s…maybe even a few 30’s over the area and highs only near 60. Temperature forecast for the weekend and early next week will depend on how much high cloud cover moves over the region from a developing tropical cyclone off the MX west coast.

Forecast models are not is very good agreement on next week as the next storm system moves into the SW US and a tropical system lingers off the MX west coast. General consensus is for a dry…cold…but possibly cloudy start to the week with air mass modification taking place by Wednesday as winds return to the south. Thanksgiving-Sunday looks potential warmer, but wet with increasingly SW slow aloft delivering disturbances across increasing moisture ahead of the next big storm system that looks to move across TX the weekend after Thanksgiving.

[weatherdude1108]

FW put up a graphic on annual rainfall



Also currently it is snowing in Amarillo, and will in Pampa later this evening. There was a tornado there 24 hours ago which preliminary surveys have EF3 from the NWS.

Looks like Austin Mabry is in second place for the all-time wettest years. 1919 takes the record with over 64 inches. Austin Bergstrom has gotten to first place (over 55 inches beating out previous record from 1957) since just after World War II when Bergstrom AFB was built and records there started. It is possible to approach first place for Mabry, but less likely climatologically these next two months, unless we get some tropical Pacific action to dump a ton load of moisture. Nothing will surprise me this year!


http://kxan.com/blog/2015/11/17/rainy-2 ... w-records/

As of Tuesday morning, November 17th, a strong storm system has brought enough rain to boost ABIA to its wettest year on record, and Camp Mabry to its second wettest. Below is an excerpt from an original post on October 26th, 2015, before the Halloween floods:

From our friend Bob Rose at the LCRA:

With the 6.03 inches of rain falling this month, this year’s annual total at Camp Mabry is now over 47 inches, making this the 9thwettest year on record. And there are still 66 days still to go. With the El Nino pattern beginning to take hold, I expect the annual total will eventually be well over 50 inches. BTW, with 40.88 inches so far at Austin-Bergstrom, it is the 15th wettest year on record at that site.

Here’s a look at the new data, with 45 days to tally left (including Nov. 17th) in 2015:

Maximum 1-Year Total Precipitation
for Austin Area, TX (ThreadEx)
Click column heading to sort ascending, click again to sort descending.
Rank Value Ending Date Missing Days
1 64.68 1919-12-31 0
2 54.79 2015-11-17 45
3 53.99 1900-12-31 0
4 52.27 2004-12-31 0
5 52.21 1991-12-31 0
6 51.73 1921-12-31 0
7 51.30 1957-12-31 0
8 51.24 1923-12-31 0
9 49.00 1913-12-31 0
10 47.28 1946-12-31 0
11 46.95 2007-12-31 0
12 46.79 1997-12-31 0
13 46.21 1941-12-31 0
14 46.05 1992-12-31 0
15 45.73 1981-12-31 0
Period of record: 1891-09-01 to 2015-11-17


Maximum 1-Year Total Precipitation
for Austin-Bergstrom Airport Area, TX (ThreadEx)
Click column heading to sort ascending, click again to sort descending.
Rank Value Ending Date Missing Days
1 55.86 2015-11-17 45
2 55.74 1957-12-31 0
3 55.24 1991-12-31 21
4 51.89 2004-12-31 0
5 50.12 1965-12-31 0
6 47.11 1992-12-31 23
7 46.47 1974-12-31 0
8 45.91 2007-12-31 0
9 44.94 1969-12-31 0
10 43.50 1994-12-31 40
11 43.12 2001-12-31 0
12 42.51 1976-12-31 0
13 42.49 1973-12-31 0
14 42.46 1981-12-31 0
15 41.87 1986-12-31 0
Period of record: 1942-10-17 to 2015-11-17

[weatherdude1108]

0.53 inches officially at my humble abode from this last event (Saturday to Tuesday). That is within the general range of the original WPC predictions.

[BrokenGlassRepublicn]

So, for those of us planning to suffer through some bad football in Austin on Thanksgiving night, what's the latest thinking?

[Ralph's Weather]

So, for those of us planning to suffer through some bad football in Austin on Thanksgiving night, what's the latest thinking?

My best guess, would be seasonable temps though will have to watch to see if the Arctic air does not try to shove its way on down early. As always with SW flow this year rain is possible. As you know we are still a ways out so much can change.

[Portastorm]

So, for those of us planning to suffer through some bad football in Austin on Thanksgiving night, what's the latest thinking?

As an ardent orangeblood, I expect bad football from the home team. And I expect a lot of offense from those Red Raiders. And I would agree with Ralph's Weather that right now it looks like seasonal temps and a chance of some light rain around. The Euro says no rain and the GFS say yes rain. Kickoff temps should be in the mid to upper 60s. And I expect Mrs. Portastorm to yell at me at least once for using non-Christian language when I see the Longhorns do their first stupid thing of the game.

[weatherdude1108]

So, for those of us planning to suffer through some bad football in Austin on Thanksgiving night, what's the latest thinking?

As an ardent orangeblood, I expect bad football from the home team. And I expect a lot of offense from those Red Raiders. And I would agree with Ralph's Weather that right now it looks like seasonal temps and a chance of some light rain around. The Euro says no rain and the GFS say yes rain. Kickoff temps should be in the mid to upper 60s. And I expect Mrs. Portastorm to yell at me at least once for using non-Christian language when I see the Longhorns do their first stupid thing of the game.

Being a scarlet and black fan myself, the Longhorns can do all the stupid things they want, IMHO. They seem to be really good at that this year. Why change up tradition now?

Of course in fairness, the Red Raiders have a history of exceeding disappointing stupid play quotas, even when they are favored by orders of magnitude.

[srainhoutx]

The 12Z NAM and GFS suggest the next front will have a bit of a bite with it regarding colder air as well as showers both pre and post frontal Saturday afternoon. Temperatures look to drop into the 40's across our Region during the early afternoon/evening Saturday. There is also a good swath of snow expected across Colorado into the Plains. Tis the season...stepping down...

[Portastorm]

YES!!

Good things are coming when srainhoutx posts and starts using the "stepping down" phrase.

[Tireman4]

The 12Z NAM and GFS suggest the next front will have a bit of a bite with it regarding colder air as well as showers both pre and post frontal Saturday afternoon. Temperatures look to drop into the 40's across our Region during the early afternoon/evening Saturday. There is also a good swath of snow expected across Colorado into the Plains. Tis the season...stepping down...

The man has spoken. The met has arisen. When he makes that statement, look out folks...