SPC AC 311244

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0744 AM CDT Fri Jul 31 2020

   Valid 311300Z - 011200Z

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LOWER MS VALLEY
   AND EASTERN NM...

   ...SUMMARY...
   Scattered damaging winds are most likely from northern Louisiana to
   northern Mississippi this afternoon. Scattered large hail and severe
   wind gusts will be possible across parts of eastern New Mexico this
   afternoon into early evening.

   ...South-central TX to the TN Valley...
   Primary shortwave trough over the Ozarks will drift east while an
   MCV over the Lower Red River Valley should reach the Ark-La-Miss
   this afternoon. Convergence will be greatest near a weak surface low
   that should slowly move east-southeast from southwest MO into
   northeast AR. However, the combination of instability and shear in
   this region should remain weak. Greater boundary-layer heating
   should occur ahead of the southern MCV amid a very moist air mass
   characterized by low to mid 70s surface dew points. This should
   yield strengthening convection this afternoon in association with
   this MCV. Given a belt of 30-40 kt 700-500 mb southwesterlies, the
   setup will support organized multicell clusters with a risk for
   scattered damaging winds.

   Farther southwest towards south-central TX, MLCAPE of 2000-2500 J/kg
   ahead of the trailing portion of the southward-pushing surface cold
   front should support locally strong gusts with isolated
   thunderstorms during the late afternoon. Weak vertical shear will
   limit the overall severe threat.

   ...NM to the TX Trans-Pecos...
   Thunderstorms will initiate off the Sangre de Cristos and Raton Mesa
   area during the early afternoon, within a weak upslope flow regime
   aided by surface dew points that should mix into the mid 40s to low
   50s. In the mid-levels, very steep lapse rates and 30-45 kt
   northerlies will support multiple discrete cells with mid-level
   updraft rotation. Scattered large hail is possible as storms spread
   relatively quickly across northeast and east-central NM. Convection
   will be outflow-dominant and may congeal into a small MCS with a
   risk for isolated to perhaps scattered severe wind gusts before
   reaching the TX Trans-Pecos this evening.

   ...VA/NC...
   Differential surface heating across an initially weak frontal
   boundary in conjunction with multiple subtle MCVs crossing the
   southern Appalachians should support isolated to scattered
   thunderstorms by early afternoon in central and southern VA into
   northern NC. A belt of 25-35 kt 700-mb westerlies will aid in
   multicell clustering. This should foster several wet microbursts
   amid a very moist air mass characterized by low to mid 70s surface
   dew points. Strong gusts producing sporadic tree damage are
   anticipated.

   ...Northern Great Plains...
   Guidance is fairly consistent in indicating isolated to scattered
   thunderstorm development along an arcing cold front from the Red
   River Valley into western SD and southeast MT. The greatest
   convergence and buoyancy should exist along the eastern Dakotas
   portion of the front. However, deep-layer shear will be weak within
   this region, suggestive of more pulse-type updrafts with a risk for
   localized severe gusts and marginally severe hail.

   Stronger effective shear will exist in the High Plains area of
   eastern MT amid 25-35 kt mid-level northwesterlies. Although
   convective coverage may remain relatively sparse in this region,
   isolated severe hail and wind are possible.

   ..Grams/Jewell.. 07/31/2020

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z