Apr 25, 2017 0600 UTC Day 1 Convective Outlook
Updated: Tue Apr 25 05:33:25 UTC 2017 (20170425 1200Z Day 1 shapefile | 20170425 1200Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20170425 1200 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SLIGHT 33,797 3,785,363 Kansas City, MO...Tulsa, OK...Overland Park, KS...Kansas City, KS...Olathe, KS...
MARGINAL 55,757 4,148,120 Oklahoma City, OK...Springfield, MO...Topeka, KS...Norman, OK...Columbia, MO...
Probabilistic Tornado Graphic
20170425 1200 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
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20170425 1200 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
15 % 33,277 3,760,100 Kansas City, MO...Tulsa, OK...Overland Park, KS...Kansas City, KS...Olathe, KS...
5 % 56,097 4,112,139 Oklahoma City, OK...Springfield, MO...Topeka, KS...Norman, OK...Columbia, MO...
Probabilistic Large Hail Graphic
20170425 1200 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
15 % 33,850 3,822,804 Kansas City, MO...Tulsa, OK...Overland Park, KS...Kansas City, KS...Olathe, KS...
5 % 56,142 4,100,230 Oklahoma City, OK...Springfield, MO...Topeka, KS...Norman, OK...Columbia, MO...
   SPC AC 250533

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1233 AM CDT Tue Apr 25 2017

   Valid 251200Z - 261200Z

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST OK
   TO WESTERN MO...

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH
   CENTRAL OK TO NORTHERN MO...

   ...SUMMARY...
   Thunderstorms capable of large hail and damaging wind are expected
   to develop across parts of northeast Oklahoma, southeast Kansas and
   western Missouri Tuesday evening, and may persist into Wednesday
   morning.

   ...Discussion...

   High-level flow is expected to increase across the southwestern US
   during the day1 period as a pronounced mid-level short-wave trough
   progresses into the southern Rockies by 26/00z.  In response to this
   feature, LLJ will increase markedly across the southern Plains which
   will allow leading edge of modified Gulf air mass to advance rapidly
   north toward a surging frontal zone over KS by peak heating. 
   However, late-evening short-range model guidance appears too
   aggressive with 60s surface dew points into southeast KS by early
   afternoon. 25/ 00z soundings at BRO and CRP are not particularly
   moist for late April with 10.7 and 9.8 g/kg mean mixing ratios
   respectively.  25/05z observational data suggests the leading edge
   of higher quality maritime air is just now surging inland across the
   lower TX coast.  Given the strength of the LLJ it appears
   moisture/instability may be a bit lower along the cold front at
   26/00z in KS than the NAM currently depicts.  Even so, strong
   boundary-layer heating will develop across the southern High Plains
   into north central OK where surface-3km lapse rates may approach dry
   adiabatic west of sharpening dry line.  For this reason it appears
   CINH will weaken sufficiently for thunderstorm development along the
   surging cold front, initially across KS, then southward into
   northern OK during the late evening hours.  Frontal forcing should
   favor linear storm mode and hail/wind appear to be the primary
   severe threats with this activity.  Robust convection should advance
   into western MO and northeast OK during the overnight hours.

   ..Darrow/Leitman.. 04/25/2017

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z