Special Special Winter Weather Winter Weather

BriefingBriefing2/8/2011 – 3 PM2/8/2011 – 3 PM

slides:slides:www.srh.noaa.gov/shv/briefingwww.srh.noaa.gov/shv/briefing

Keith StellmanKeith Stellman

National Weather Service Shreveport, LouisianaNational Weather Service Shreveport, Louisiana

Summary - Wednesday/Wednesday NightSummary - Wednesday/Wednesday Night Upper level trough pushes a strong cold front across the Upper level trough pushes a strong cold front across the

area while a surface low develops along the northern Gulf of area while a surface low develops along the northern Gulf of Mexico…enhancing lift and moisture into the region.Mexico…enhancing lift and moisture into the region.

Accumulations of 6” - 8” McCurtain, Little River, Howard, Accumulations of 6” - 8” McCurtain, Little River, Howard, Sevier, Hempstead, NevadaSevier, Hempstead, Nevada

Accumulations of 4” - 6” Remaining AR Counties, I-30 NE TXAccumulations of 4” - 6” Remaining AR Counties, I-30 NE TX Accumulations of 2” - 4” Along and north of a Jacksonville -Accumulations of 2” - 4” Along and north of a Jacksonville -

> Henderson -> Carthage -> Mansfield/Coushatta -> Henderson -> Carthage -> Mansfield/Coushatta ->Jonesboro ->Columbia Line.>Jonesboro ->Columbia Line.

Accumulations of ~1” southern Parishes in LA/ Deep East TXAccumulations of ~1” southern Parishes in LA/ Deep East TX

TIMINGTIMING NE TX/SE OK after Midnight (Wed)NE TX/SE OK after Midnight (Wed) Sleet/snow starting in LA/South Central AR ~ 7 - 9 AM WedSleet/snow starting in LA/South Central AR ~ 7 - 9 AM Wed Monroe/El Dorado – Light Mix in the AM, changeover 2 - 4 Monroe/El Dorado – Light Mix in the AM, changeover 2 - 4

PMPM

National Weather Service Shreveport, LouisianaNational Weather Service Shreveport, Louisiana

Big PictureBig Picture

National Weather Service Shreveport, LouisianaNational Weather Service Shreveport, Louisiana

TodaTodayy

TonightTonightWednesdWednesd

ayay

Upper level disturbance

HHArctic Surface High

How is it going to snow with How is it going to snow with temps in the 50’s today!!temps in the 50’s today!!

Noon Temperature profile - SHVNoon Temperature profile - SHV Entire Entire

column column is cool is cool above above 1500 1500 feetfeet

Its only Its only warm warm below below 1500 1500 feetfeet

Height

Tem

peratu

re

Free

zing

line

Current Snow Pack – 2/8/11Current Snow Pack – 2/8/11

Snowpack extends far to

the south..helping maintain arctic

air

Sleet/Snow/RainSleet/Snow/Rain Temperature profile at 6 AM Wed Temperature profile at 6 AM Wed

( (LufkinLufkin - - TylerTyler))

Free

zing

lin

e

Sleet Sleet starting at starting at Tyler…to Tyler…to snow late snow late AMAM

Warm Air Warm Air below below 6000 feet 6000 feet at LFK at LFK suggests suggests all rainall rainHeight

Surface Temperatures 29-32

Sleet/SnowSleet/Snow Temperature profile at 6 AM Wed Temperature profile at 6 AM Wed

( (Mt PleasantMt Pleasant - - TexarkanaTexarkana))

Free

zing

line

Sleet Sleet starting at starting at Mt Mt Pleasant Pleasant to snow to snow early in early in the AMthe AM

Texarkana Texarkana and and locations locations in the US in the US 82 82 Corridor Corridor all snowall snow

Height

Surface Temperatures 28-32

Sleet/snowSleet/snowTemperature profile at NoonTemperature profile at Noon

ShreveportShreveport - - Monroe Monroe

Free

zing

lin

e

Shreveport Shreveport All snow by All snow by noonnoon Starting Starting

as sleet as sleet in the in the AMAM

Monroe not Monroe not saturated saturated at at noon..but noon..but quickly quickly becoming becoming so. Precip so. Precip starting starting after Noonafter Noon

Height

Surface Tempeatures 29-32

Surface Temps 33-36

Sleet/RainSleet/Rain Temperature profile at Noon Wed Temperature profile at Noon Wed

( (NatchitochesNatchitoches))

Free

zing

line

Mostly Mostly rain… rain… changing changing to to sleet/snosleet/snow at the w at the end. end. Late Late afternoon afternoon WEDWED

Warm Air Warm Air below below 6000 feet 6000 feet at NAT at NAT suggests suggests all rainall rain

Height

Surface Temperatures 33-36

National Center Snow Forecast National Center Snow Forecast 6 AM Forecast6 AM Forecast

Amounts Amounts have trended have trended up and up and slightly slightly southsouth

Newest runs Newest runs - 1 PM - 1 PM (internal (internal graphic ..the graphic ..the 3” line is 3” line is now 4”)now 4”) Higher Higher

amounts amounts further further southsouth

1”- 2”

2”-4 ”

>4”

AmountsAmounts

TimingTimingOnsetOnset and and ChangeoverChangeover

12 AM – 4 AM12 AM – 4 AM

4 AM – 7AM4 AM – 7AM

7 AM – 10AM7 AM – 10AM

10 AM – 1 PM10 AM – 1 PM 2 PM – 5 PM2 PM – 5 PM

Noon – 2 PMNoon – 2 PM

Wed Temperatures Wed Temperatures

Noon 3 PM

Wed-Thu TemperaturesWed-Thu TemperaturesWED 6 PM Lows Thu AM

Thursday-Friday TempsThursday-Friday Temps

Thu Highs Fri AM Lows

Snow will start in the Snow will start in the Northwest (NE TX/SE Northwest (NE TX/SE OK) after Midnight (Wed)OK) after Midnight (Wed)

Sleet/snow starting in Sleet/snow starting in LA/South Central AR ~ 6-LA/South Central AR ~ 6-8 AM Wed 8 AM Wed

Sleet/snow starting in Sleet/snow starting in Monroe/ELD ~2 PMMonroe/ELD ~2 PM

Lower visibilitiesLower visibilities

Ground temps ~40.5/37 Ground temps ~40.5/37 in AR… in AR…

Precip will likely stick to Precip will likely stick to surfaces similar to the surfaces similar to the last event…especially last event…especially where the rate is higherwhere the rate is higher

Cold Temps through Thu Cold Temps through Thu will keep it around into will keep it around into Friday when temps Friday when temps rebound into the 40srebound into the 40s

Clouds early on Thu..sun Clouds early on Thu..sun by midday. Hazardous by midday. Hazardous travel early Thutravel early Thu

ImpactsImpacts

NEXT CONFERENCE CALL:

Wednesday @ 9 AM Wednesday @ 9 AM www.srh.noaa.gov/shv/briewww.srh.noaa.gov/shv/brie

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National Weather Service Shreveport, LouisianaNational Weather Service Shreveport, Louisiana