March '10 Weather Discussion

[venture]

why are they SHOUTING the forecast?!?!

Yeah, every NOAA product is in caps. I think it is to ensure certain errors don't occur when it comes to I/L type mistakes. The board will sometimes put everything in all lower case, but sometimes it doesn't...and I'm not retyping everything. :-P

[venture]

New Day 1 should be out soon, but here is the watch for Eastern OK.



URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 20
NWS STORM PREDICTION CENTER NORMAN OK
1240 PM CDT WED MAR 10 2010

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

WESTERN ARKANSAS
PARTS OF NORTHWEST LOUISIANA
EASTERN OKLAHOMA
PARTS OF NORTHEAST TEXAS

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 1240 PM UNTIL
600 PM CDT.

WIDELY SCATTERED DAMAGING WINDS
ISOLATED WIND GUSTS TO 70 MPH POSSIBLE
SCATTERED LARGE HAIL
ISOLATED HAIL TO 2.5 INCHES IN DIAMETER POSSIBLE
ISOLATED TORNADOES

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65
STATUTE MILES EAST AND WEST OF A LINE FROM 70 MILES SOUTH
SOUTHEAST OF LONGVIEW TEXAS TO 50 MILES NORTHWEST OF FAYETTEVILLE
ARKANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 19...

DISCUSSION...INTENSE UPPER TROUGH MOVING EWD ACROSS OK/N TX THIS
AFTERNOON WITH RAPIDLY DESTABILIZING AIR MASS ACROSS THE WATCH AREA.
THUNDERSTORMS NOW NCENTRAL TX/SRN OK EXPECTED TO INTENSIFY THRU THE
AFTERNOON AS THEY MOVE/DEVELOP NEWD. WITH STEEP LAPSE RATES AND
MLCAPES CLIMBING TO 1000 J/KG...THREAT OF LARGE HAIL AND DAMAGING
WINDS WILL INCREASE.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 24035.

[venture]

Anything that pops up around here should be below severe limits as it looks right now.



Dryline pushing through most of the SW part of the state into the Metro now.



OUN's Summary of the wide variety of weather right now. lol

[westsidesooner]

The last two systems (Monday and today) have been very strong and very tightly wound lows.....can you imagine the amount of severe weather they would have caused if they had come thru later in April or May. I wonder if these strong lows are an indication of what to expect later in the spring?

[Thunder]

Live Wire | Oklahoma Live Wire -- KOCO.com Breaking News, Weather (Mar. 10)

Join the Live Wire. We have streaming video posted. Chris Lee is tracking a tornadic cell near Stillwater.

[venture]

Umm...to be tornadic, typically it has to produce something that resembles a tornado. :-P

[silvergrove]

Live Wire | Oklahoma Live Wire -- KOCO.com Breaking News, Weather (Mar. 10)

Join the Live Wire. We have streaming video posted. Chris Lee is tracking a tornadic cell near Stillwater.

LMAO, you were the one who posted that cow photoshop?

[Thunder]

LMAO, you were the one who posted that cow photoshop?

Yes. No storm is complete without a cow.

I posted one for the Monday's tornado.

Venture, you may want to look again. :-O

[venture]

Perhaps if that picture was actually from today, you might have something. You can post what you want on KOCO's site, but let's try to keep this thread factual without bogus crap.

[venture]

Bulletin - immediate broadcast requested
severe thunderstorm warning
national weather service norman ok
407 pm cst wed mar 10 2010

the national weather service in norman has issued a

* severe thunderstorm warning for...
Kay county in northern oklahoma...
Northeastern noble county in northern oklahoma...

* until 445 pm cst

* at 407 pm cst...national weather service radar indicated severe
thunderstorms along a line extending from 13 miles northwest of
marland to 5 miles south of ponca city to 5 miles north of sooner
lake...moving northeast at 40 mph.

Hazards in the warning include...
Hail up to the size of quarters...
Wind gusts to 60 mph...

* locations in the warning include chilocco...hardy...kaw city...kaw
lake...kildare...marland...newkirk...peckham...pon ca city and
sooner lake.

[Thunder]

It's the storm from today near Stillwater. I stretched out the clouds to form a tornado. lolol

Here one for fun.

[venture]

Not really weather related, but...

[blangtang]

crazy mike says we're in for a big snowstorm later this week. i don't believe him!

[Thunder]

crazy mike says we're in for a big snowstorm later this week. i don't believe him!

It's true. The guys down in NWS is in major shock according to latest models. We're having another blizzard!

[PennyQuilts]

I just saw the forecast. That is just wrong. WRONG.

[venture]

A pretty dynamic system coming in this week and we'll see all colors of the Oklahoma weather spectrum.

[venture]

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0213 AM CDT WED MAR 17 2010

VALID 191200Z - 201200Z

...SYNOPSIS...
ALTHOUGH ONE STRONG SHORT WAVE TROUGH LIFTING TOWARD THE BRITISH
COLUMBIA COAST...AND ANOTHER DIGGING OUT OF THE NORTHWEST
TERRITORIES...MAY CONTRIBUTE TO WEAKENING...MODELS SUGGEST THAT
AMPLIFIED RIDGING WILL PERSIST ALONG THE PACIFIC COAST THROUGH THIS
PERIOD. AND A STRONG DOWNSTREAM SHORT WAVE TROUGH APPEARS LIKELY TO
CONTINUE DIGGING SOUTH SOUTHEASTWARD FROM THE GREAT BASIN THROUGH
THE SOUTHERN PLAINS BY 12Z SATURDAY. THIS FEATURE IS PROGGED TO BE
ACCOMPANIED BY A STRONG COLD INTRUSION TO THE LEE OF THE
ROCKIES...THE LEADING EDGE OF WHICH IS EXPECTED TO PROVIDE THE FOCUS
FOR A DEVELOPING SURFACE LOW ACROSS THE RED RIVER VALLEY INTO THE
OZARK PLATEAU FRIDAY NIGHT.

A FAIRLY DEEP INITIAL SURFACE LOW IS PROGGED TO MIGRATE SOUTH
SOUTHEASTWARD THROUGH THE SOUTH CENTRAL HIGH PLAINS DURING THE DAY
FRIDAY...AS DOWNSTREAM SURFACE RIDGING RETREATS EASTWARD TOWARD THE
WESTERN ATLANTIC. AS THIS OCCURS...A BROADENING BELT OF MODESTLY
STRONG SOUTHERLY FLOW WILL DEVELOP OFF THE GULF OF MEXICO THROUGH
MUCH OF THE SOUTH CENTRAL STATES. HOWEVER...AN INITIALLY RELATIVELY
DRY BOUNDARY LAYER OVER THE GULF OF MEXICO WILL TAKE TIME TO
MODIFY...AND SREF GUIDANCE SUGGESTS THAT SURFACE DEW POINTS OF 55F
MAY NOT REACH MUCH BEYOND TEXAS COASTAL AREAS BY THE END OF THE
PERIOD...WITH DEW POINTS GENERALLY IN THE MID 50S TO LOWER 60S
ACROSS THE NORTHWEST GULF.

THE LACK OF A SUBSTANTIVE RETURN FLOW STILL APPEARS LIKELY TO LIMIT
THE CONVECTIVE POTENTIAL WITHIN AN EVOLVING LARGE-SCALE PATTERN THAT
MIGHT MORE TYPICALLY BE ASSOCIATED WITH A MORE SIGNIFICANT SEVERE
WEATHER THREAT. BUT...THE RISK FOR SEVERE STORMS MAY NOT BE
COMPLETELY NEGLIGIBLE.

...SOUTH CENTRAL PLAINS...
IF THE SURFACE COLD FRONT DOES NOT ADVANCE SOUTHWARD TOO MUCH FASTER
THAN CURRENTLY SUGGESTED BY THE MODELS...AN AXIS OF STRONGER SURFACE
HEATING /TO AROUND 70F/ APPEARS LIKELY BENEATH A NORTHEASTWARD
ADVECTING ELEVATED MIXED LAYER...FROM THE TEXAS SOUTH PLAINS THROUGH
WESTERN OKLAHOMA...PERHAPS SOUTH CENTRAL KANSAS...BY LATE FRIDAY
AFTERNOON. COUPLED WITH A NARROW WEAK TONGUE OF MOISTENING
/PRECIPITABLE WATER OF .5 TO .75 INCHES...SFC DEW POINTS NEAR
50F/...CONDITIONAL AND CONVECTIVE INSTABILITY EVIDENT IN FORECAST
SOUNDINGS APPEARS SUFFICIENT FOR VIGOROUS CONVECTIVE DEVELOPMENT.
THE PRIMARY MID-LEVEL COOLING MAY STILL LAG TO THE NORTH AND
WEST...BUT WEAKENING INHIBITION IN THE PEAK HEATING COMBINED WITH
FRONTAL FORCING PROBABLY WILL CONTRIBUTE TO THE INITIATION OF
CONVECTIVE DEVELOPMENT.

SOME STORMS MAY BE CAPABLE OF PRODUCING MARGINALLY SEVERE HAIL.
HOWEVER...THE PRIMARY SEVERE CONCERN MAY BE POTENTIALLY DAMAGING
WIND GUSTS...AS SIZABLE LOWER/MID TROPOSPHERIC TEMPERATURE/DEW POINT
SPREADS ENHANCE EVAPORATIVE COOLING IN DOWNDRAFTS WITHIN A NARROW
EVOLVING SQUALL LINE. AS ACTIVITY DEVELOPS EASTWARD...THE SEVERE
THREAT MAY CONTINUE INTO THE EVENING HOURS...BEFORE THE FRONT
PERHAPS UNDERCUTS THE CONVECTION AND/OR ACTIVITY BEGINS TO SPREAD
EAST OF THE MOIST AXIS...INGESTING DRIER AIR.

...PARTS OF NORTH CENTRAL/EASTERN TEXAS...
A SEPARATE AREA OF VIGOROUS CONVECTIVE DEVELOPMENT SEEMS POSSIBLE
ACROSS THE REGION PRIOR TO 12Z SATURDAY...WITHIN A STRENGTHENING
ELEVATED WARM ADVECTION REGIME...AS STRONGER MID/UPPER FORCING
FINALLY BEGINS TO SURGE EASTWARD ACROSS THE SOUTHERN PLAINS. THIS
MAY BE AIDED BY A SOMEWHAT BETTER INFLUX OF GULF MOISTURE ON THE
STRENGTHENING LOW-LEVEL JET...AND INSTABILITY COUPLED WITH
STRENGTHENING DEEP LAYER SHEAR MAY CONTRIBUTE TO A RISK FOR LARGE
HAIL.

..KERR.. 03/17/2010

[sacolton]

What's this **** about a SNOW STORM on Saturday?!!! Venture, give us the truth!!!

[venture]

Snow storm? Ehh. Storms with snow after sounds better. LOL

Generally what we are looking at is Friday will see the cold front get to the Metro by late afternoon/early evening. Storms will fire ahead, some will probably be in severe limits with hail and wind. We'll then see extreme temp drops behind the front which will change precip over to snow in areas. Places that see convective snow (thundersnow) and other heavier pockets will get some accumulation on streets and such. Otherwise, most areas will see accumulation limited to elevated/grassy surfaces.

Both NAM and GFS show a good swath of accumulation across the state, but PLEASE remember...its going to be near 70 tomorrow and the ground is fairly warm as is. GFS is extremely aggressive, so I would take it with a bucket of salt.

NAM: 1-2" from I-40 and North. 3-4" across NW and most of Northern OK.
GFS: Most of OK at least 1". Western half of OK 3-5", Eastern half 6-12".

I'm not buying GFS's snowfall forecast since it is probably overdoing precip a bit and being a tad slow with moving the system out. Here is a more specific look at the two, highlight time periods where change over occurs and accumulations there after...all Metro specific...

GFS - Worst case snowfall: 5-8"
Friday 7PM - Scattered showers/storms. Temps low 60s.
Saturday 4AM - Rain mixing with some snow. Temps upper 30s.
Saturday 7AM - Snow with some rain mixing. Temps low 30s. 0.2-0.3" Liquid Accumulation.
Saturday 1PM - Light snow. Temps low 30s. 0.2" liquid accumulation.
Saturday 7PM - Light snow. Temps low 30s. 0.1" liquid accumulation.
Sunday 1AM - Light snow. Temps upper 20s. 0.1-0.2" liquid accumulation.
Sunday 7AM - Light snow ending. Temps around 30. 0.1" liquid accumulation.
Remainder of Sunday...Snow mainly east of I-35 and south of I-44. Some areas may be heavy according to GFS.

NAM - Worst case snowfall: 2-3"
Friday 7PM - Scattered Showers and Storms developing ahead of Cold Front. Some strong, maybe severe.
Saturday 7AM - Moderate to Heavy Rain, some wet snow mixing in. Temps mid 30s.
Saturday 10AM - Snow mixing with rain. Temps low to mid 30s. Around 0.2-0.4 liquid accumulation.
Saturday 1PM - Light snow/flurries. Temps low 30s. Less than 0.1" liquid accumulation.
Rest of Saturday through early Sunday. Light snow/flurries/snow showers throughout the period. Maybe 0.1 to 0.2 of additional liquid accumulation at the most.

[oknacreous]

Two other things about this storm will be the sudden sharp temperature drop around sunset Friday, and the long duration strong winds that start at the same time and last through the day Saturday - frequent gusts 40-50 mph appear likely. The snow should be fairly wet and with the strong winds, there could be some power line/tree branch issues. As far as snow amounts go, I've sliced and diced this one every way I know at work today, and it appears the models are trending strongly toward more snow on Saturday, the question now is how much. North central OK up into the Kansas City area appear likely to get very high amounts of 10 inches or more. OKC is a bit more dicey but the info I'm seeing now suggests at least 2-4" metro-wide with maybe up to 7-8", particularly north side of OKC.

[oknacreous]

The new run of the European model dumps a foot of snow with high winds on OKC Saturday.

[venture]

The new run of the European model dumps a foot of snow with high winds on OKC Saturday.

Mmmhmm. So about that worst case scenario. lol

If models keep trending, we'll probably see Winter Storm Watches hoisted later today.

[rod4soonrs]

[sacolton]

ARGGHH! Gotta fire up the furnace again!

[oknacreous]

The winter storm watch is now posted, includes all of the OKC metro.