Feb 20, 2019 2000 UTC Day 1 Convective Outlook
Updated: Wed Feb 20 19:44:09 UTC 2019 (20190220 2000Z Day 1 shapefile | 20190220 2000Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20190220 2000 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 20,654 2,116,786 New Orleans, LA...Metairie, LA...Gulfport, MS...Kenner, LA...Hattiesburg, MS...
Probabilistic Tornado Graphic
20190220 2000 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
2 % 17,827 1,337,816 Metairie, LA...Gulfport, MS...Kenner, LA...Hattiesburg, MS...Biloxi, MS...
Probabilistic Damaging Wind Graphic
20190220 2000 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Day 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 20,850 2,135,375 New Orleans, LA...Metairie, LA...Gulfport, MS...Kenner, LA...Hattiesburg, MS...
Probabilistic Large Hail Graphic
20190220 2000 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Day 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
   SPC AC 201944

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0144 PM CST Wed Feb 20 2019

   Valid 202000Z - 211200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
   SOUTHEAST LOUISIANA...SOUTHERN MISSISSIPPI AND WESTERN ALABAMA...

   ...SUMMARY...
   An isolated strong to severe storm could produce gusty winds through
   the remainder of the afternoon from southeast Louisiana into
   southern Mississippi and western Alabama.

   ...Southeast LA into MS/AL...

   Widespread cloud cover continues to inhibit destabilization across
   the northern Gulf Coast. Latest mesoanalysis indicates MLCAPE less
   than 1000 J/kg, despite surface dewpoints in the mid 60s to near 70
   F.  Additionally, the absence of stronger forcing, severe potential
   appears to be limited across the region. As such, the Slight risk
   has been removed as have hail probabilities. A narrow corridor from
   southeast LA into western AL could still produce a stronger storm
   capable mainly of gusty winds over the next few hours before the
   severe threat diminishes completely late this afternoon.

   ..Leitman.. 02/20/2019

   .PREV DISCUSSION... /ISSUED 1030 AM CST Wed Feb 20 2019/

   ...Southeast Louisiana and portions of Mississippi/Alabama...
   A 1008 mb-surface low related triple point exists across
   south-central MS at late morning, with upper 60s/near 70 F surface
   dewpoints within the warm sector across southern MS/southeast LA.
   Deep-layer/low-level shear are notably strong, with strong low-level
   shear/SRH accentuated by the entrance region of a 50+ kt
   southwesterly low-level jet, which will tend to slowly weaken and
   spread away from the warm sector during the afternoon. 

   Organization/rotation-favorable shear aside, persistent dense cloud
   cover will tend to hinder insolation, which will in turn dampen
   upward parcel accelerations and the overall thermodynamic
   environment. Stronger forcing for ascent will also be focused north
   of the region, with neutral if not rising upper heights by late
   afternoon/early evening.

   These offsetting factors suggest the severe risk should remain very
   localized and limited today, although sufficient buoyancy amidst
   strong shear will pose at least a conditional/isolated severe risk
   mainly in the form of locally damaging winds and some tornado risk,
   primarily through the early/mid part of the afternoon.

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z