Special Winter Weather Briefing 2/8/2011 – 3 PM slides: srh.noaa/shv/briefing

1. Special Winter Weather Briefing2/8/2011 – 3 PMslides:www.srh.noaa.gov/shv/briefing Keith Stellman National Weather Service Shreveport, Louisiana

2. Summary - Wednesday/Wednesday Night Upper level trough pushes a strong cold front across the area while a surface low develops along the northern Gulf of Mexico…enhancing lift and moisture into the region. Accumulations of 6” - 8” McCurtain, Little River, Howard, Sevier, Hempstead, Nevada Accumulations of 4” - 6” Remaining AR Counties, I-30 NE TX Accumulations of 2” - 4” Along and north of a Jacksonville -> Henderson -> Carthage -> Mansfield/Coushatta ->Jonesboro ->Columbia Line. Accumulations of ~1” southern Parishes in LA/ Deep East TX TIMING NE TX/SE OK after Midnight (Wed) Sleet/snow starting in LA/South Central AR ~ 7 - 9 AM Wed Monroe/El Dorado – Light Mix in the AM, changeover 2 - 4 PM National Weather Service Shreveport, Louisiana

3. Big Picture H Arctic Surface High Upper level disturbance L Today L L Tonight Wednesday National Weather Service Shreveport, Louisiana

5. How is it going to snow with temps in the 50’s today!!Noon Temperature profile - SHV • Entire column is cool above 1500 feet • Its only warm below 1500 feet Temperature Height Freezing line

6. Current Snow Pack – 2/8/11 Snowpack extends far to the south..helping maintain arctic air

7. Sleet/Snow/Rain Temperature profile at 6 AM Wed (Lufkin - Tyler) • Sleet starting at Tyler…to snow late AM • Warm Air below 6000 feet at LFK suggests all rain Freezing line Surface Temperatures 29-32 Height

8. Sleet/Snow Temperature profile at 6 AM Wed (Mt Pleasant - Texarkana) • Sleet starting at Mt Pleasant to snow early in the AM • Texarkana and locations in the US 82 Corridor all snow Freezing line Surface Temperatures 28-32 Height

9. Sleet/snowTemperature profile at NoonShreveport- Monroe • Shreveport All snow by noon • Starting as sleet in the AM • Monroe not saturated at noon..but quickly becoming so. Precip starting after Noon Freezing line Surface Tempeatures 29-32 Surface Temps 33-36 Height

10. Sleet/Rain Temperature profile at Noon Wed (Natchitoches) • Mostly rain… changing to sleet/snow at the end. Late afternoon WED • Warm Air below 6000 feet at NAT suggests all rain Freezing line Surface Temperatures 33-36 Height

11. National Center Snow Forecast 6 AM Forecast • Amounts have trended up and slightly south • Newest runs - 1 PM (internal graphic ..the 3” line is now 4”) • Higher amounts further south >4” 2”-4 ” 1”- 2”

12. Amounts

13. 12 AM – 4 AM Timing Onset and Changeover 4 AM – 7AM Noon – 2 PM 7 AM – 10AM 2 PM – 5 PM 10 AM – 1 PM

14. Wed Temperatures Noon 3 PM

15. Wed-Thu Temperatures WED 6 PM Lows Thu AM

16. Thursday-Friday Temps Thu Highs Fri AM Lows

17. Impacts • Lower visibilities • Ground temps ~40.5/37 in AR… • Precip will likely stick to surfaces similar to the last event…especially where the rate is higher • Cold Temps through Thu will keep it around into Friday when temps rebound into the 40s • Clouds early on Thu..sun by midday. Hazardous travel early Thu • Snow will start in the Northwest (NE TX/SE OK) after Midnight (Wed) • Sleet/snow starting in LA/South Central AR ~ 6-8 AM Wed • Sleet/snow starting in Monroe/ELD ~2 PM

18. NEXT CONFERENCE CALL: Wednesday @ 9 AM www.srh.noaa.gov/shv/briefing National Weather Service Shreveport, Louisiana