Aug 4, 2022 2000 UTC Day 1 Convective Outlook
Updated: Thu Aug 4 19:40:03 UTC 2022 (20220804 2000Z Day 1 shapefile | 20220804 2000Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20220804 2000 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 335,524 45,209,241 Columbus, OH...Baltimore, MD...Washington, DC...Las Vegas, NV...Nashville, TN...
Probabilistic Tornado Graphic
20220804 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
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20220804 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 % 334,871 45,207,249 Columbus, OH...Baltimore, MD...Washington, DC...Las Vegas, NV...Nashville, TN...
Probabilistic Large Hail Graphic
20220804 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
5 % 47,576 346,371 Flagstaff, AZ...Prescott Valley, AZ...Sedona, AZ...Cottonwood, AZ...Camp Verde, AZ...
   SPC AC 041940

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0240 PM CDT Thu Aug 04 2022

   Valid 042000Z - 051200Z


   Isolated severe thunderstorms, mainly in the form of damaging winds,
   are possible into early evening from the Ohio Valley into parts of
   the Mid-Atlantic and New England, western portions of South Dakota
   and Nebraska, Montana, and the western Colorado Plateau.

   ...20Z Update...

   ...OH Valley into the Mid-Atlantic and New England...
   A few stronger gusts have been noted sporadically with a few storms
   over the past hour or so, including a 42 kt gust at IPT in central
   PA and a 40 kt gust at BGM in south-central NY. This trend will
   likely continue throughout the afternoon within the unstable but
   weakly sheared air mass over the region. Additional short-term
   information is available in recently issued MCD #1651.

   Farther west in the Lower OH Valley, a well-defined MCV is slowly
   moving northeastward. Some limited enhancement of the low to
   mid-level flow is possible through its eastern periphery, supporting
   the potential for isolated stronger storms capable of damaging wind
   gusts over southern IN and adjacent western KY through the

   Forecasts outlined in the previous outlook remain valid. See
   previous discussion below for details.

   ..Mosier.. 08/04/2022

   .PREV DISCUSSION... /ISSUED 1121 AM CDT Thu Aug 04 2022/

   Strong surface heating and deep mixing will occur along a surface
   lee trough across from the NE Panhandle into southwest SD. Though
   boundary-layer moisture will be somewhat marginal, a narrow corridor
   of MLCAPE approaching 1500 J/kg should develop with minimal MLCIN.
   Most CAM guidance suggest a few storms should form near the surface
   trough during the late afternoon. Inverted-v thermodynamic profiles
   and moderately elongated hodographs could support a couple
   high-based supercells capable of isolated severe wind and hail for a
   few hours into the early evening.

   An amplified upper trough centered on BC will shift east across the
   Canadian Rockies towards SK through 12Z tomorrow. As this occurs, a
   surface cyclone will deepen over southeast AB into southern SK, with
   a trailing cold front sharpening over MT. With PW values largely
   between 0.5 to 0.75 inches this morning, boundary-layer moisture
   will be quite limited. Very deep boundary-layer mixing with meager
   buoyancy atop that along the surface front should be just enough to
   promote very high-based convection from southwest to central MT.
   While the bulk of stronger mid-level westerlies will be confined to
   the cool side of the surface front, adequate strengthening will
   support semi-organized skeletal clusters capable of isolated severe
   outflow gusts spreading east-northeast.

   ...OH Valley into the Mid-Atlantic and New England...
   A remnant MCV over far southern IL should drift east into western
   KY. To the northeast of this MCV, broad but weak mid-level
   southwesterlies will exist within a seasonably rich PW moisture
   plume. The persistence of weak convective outflows, differential
   surface heating, and terrain will support a broad swath of scattered
   thunderstorms. Relatively greater potential for damaging microbursts
   in predominately pulse and slow-moving multicell clusters should
   exist from the Upper OH Valley into the Northeast/Mid-Atlantic where
   MLCAPE can exceed 2000 J/kg. But the lack of greater vertical shear
   will be detrimental to an organized severe threat. See MCD 1648 and
   later MCDs this afternoon for additional short-term forecast

   ...Western CO Plateau vicinity...
   A belt of enhanced mid-level easterlies becoming more southeasterly
   later today will persist to the north of an MCV drifting west across
   the Lower CO Valley. Scattered thunderstorms are expected to develop
   northwestward off the Mogollon Rim across the western CO Plateau and
   spread towards the southern Great Basin. Marginally severe hail will
   possible in initial updrafts transitioning to mainly a marginally
   severe wind threat later.