May 27, 2020 1630 UTC Day 1 Convective Outlook
Updated: Wed May 27 16:18:33 UTC 2020 (20200527 1630Z Day 1 shapefile | 20200527 1630Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20200527 1630 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
ENHANCED 26,684 2,979,695 Austin, TX...Waco, TX...Killeen, TX...Round Rock, TX...College Station, TX...
SLIGHT 30,267 7,957,248 Houston, TX...San Antonio, TX...Pasadena, TX...Sugar Land, TX...The Woodlands, TX...
MARGINAL 176,576 18,340,109 New Orleans, LA...Atlanta, GA...Birmingham, AL...Durham, NC...Montgomery, AL...
Probabilistic Tornado Graphic
20200527 1630 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
5 % 25,279 2,676,899 Austin, TX...Waco, TX...Killeen, TX...Round Rock, TX...College Station, TX...
2 % 67,782 12,580,365 Houston, TX...San Antonio, TX...Raleigh, NC...Durham, NC...Pasadena, TX...
Probabilistic Damaging Wind Graphic
20200527 1630 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
SIG SEVERE 24,575 2,997,270 Austin, TX...Waco, TX...Killeen, TX...Round Rock, TX...College Station, TX...
30 % 24,594 2,954,791 Austin, TX...Waco, TX...Killeen, TX...Round Rock, TX...College Station, TX...
15 % 30,118 7,913,636 Houston, TX...San Antonio, TX...Pasadena, TX...Sugar Land, TX...The Woodlands, TX...
5 % 179,166 18,613,940 New Orleans, LA...Atlanta, GA...Birmingham, AL...Durham, NC...Montgomery, AL...
Probabilistic Large Hail Graphic
20200527 1630 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
SIG SEVERE 38,932 4,491,034 San Antonio, TX...Austin, TX...Waco, TX...Killeen, TX...Round Rock, TX...
30 % 23,010 2,671,659 Austin, TX...Waco, TX...Killeen, TX...Round Rock, TX...Temple, TX...
15 % 33,665 8,217,123 Houston, TX...San Antonio, TX...Pasadena, TX...College Station, TX...Sugar Land, TX...
5 % 134,011 9,842,604 New Orleans, LA...Birmingham, AL...Montgomery, AL...Mobile, AL...Columbus, GA...
   SPC AC 271618

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1118 AM CDT Wed May 27 2020

   Valid 271630Z - 281200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
   AND EVENING OVER PARTS OF TEXAS...

   ...SUMMARY...
   Severe thunderstorms are expected today over central Texas and
   vicinity, where very large hail, severe wind, and a few tornadoes
   possible.

   ...TX...
   An upper low is present today over northeast TX, with a band of
   stronger northwesterly flow aloft extending from northwest into
   southeast TX.  Model guidance suggests that mid level heights will
   rise through the day, but that several smaller-scale vorticity
   maxima are rotating around the upper low and will affect central TX.
   These will lead to clusters of intense thunderstorms from early
   afternoon through evening.

   A few storms have already begun to form south of the Dallas-Ft Worth
   area.  More widespread storms will develop by mid afternoon as the
   air mass continues to moisten/destabilize.  Low level winds will not
   be particularly strong, but deep layer shear will be favorable for
   organized/rotating storms.  This combined with MLCAPE values of 2500
   J/kg will pose a risk of very large hail.  Damaging wind potential
   should increase during the evening as storms congeal and spread
   toward the middle/upper TX Gulf Coast.

   ...Gulf Coast States...
   A very moist and moderately unstable air mass is in place today from
   LA/MS eastward into parts of AL/FL/GA.  A weak upper trough off the
   LA coast will lift northeastward today, providing subtle lift across
   the region and helping to initiate scattered thunderstorms.  Mid and
   upper level winds are stronger than yesterday, which may help the
   more intense storms to organize and pose a risk of locally
   strong/damaging wind gusts.

   ...SC/NC...
   TS Bertha has moved inland over SC, and will continue to drift
   slowly northward.  The envelope of stronger low-level winds is
   small, and the convective nature of storms have shown little
   tendency for cellular structures thus far.  Nevertheless, will
   maintain a narrow corridor of MRGL risk for brief tornadoes through
   the afternoon and evening where CAM solutions suggest there is some
   potential.

   ..Hart/Bentley.. 05/27/2020

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