NOAA Storm Prediction Center
Convective Outlooks
Convective Outlooks
The convective outlooks serve as guidance to the local NWS forecast offices and are used by emergency managers, private sector meteorologists, media, and other weather customers concerned with public safety. Three separate risk areas (slight, moderate, and high) are used to describe the expected coverage and intensity for the categorical severe weather threat on days 1-3 along with severe weather probabilities for the potential threat.
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Categorical Day1 2000Z Outlook
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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.
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Probability of one inch diameter hail or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of two inch diameter hail or larger within 25 miles of a point.
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Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% or greater probability of wind gusts 65 knots or greater within 25 miles of a point.
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Images courtesy of the NWS Storm Prediction Center
000
ACUS01 KWNS 021951
SWODY1
SPC AC 021949
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Fri Jun 02 2023
Valid 022000Z - 031200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE TX
SOUTH PLAINS INTO THE EDWARDS PLATEAU...
...SUMMARY...
A few tornadoes, destructive baseball to softball sized hail, and
scattered severe wind gusts to around 75 mph will be possible across
parts of the southern High Plains into this evening.
...20Z Update...
...Southern High Plains...
Overall forecast outlined in the previous discussion (appended
below) remains valid. Higher thunderstorm coverage across and more
linear storm structure has materialized across the western TX
Panhandle, with more discrete activity farther south across far
southeast NM into west TX.
A tornado has been reported with the supercells in Gaines and Pecos
Counties in Texas, with large hail reported in these storms as well
as the other more discrete storms across the region. A trend towards
additional upscale growth is anticipated with this more discrete
activity entering the TX South Plains. All severe hazards are
possible before this transition occurs, with the primary threat then
becoming damaging gusts. There is also some potential for the lone
storm in Pecos county to eventually trend more linear and progress
southeastward.
Additional storm development is ongoing back farther west over the
higher terrain, with at least some potential for additional hail and
a strong gusts or two as it gradually moves eastward this afternoon
and evening.
...Eastern MT...
Recently issued MCD #922 addresses this region, where a marginal
wind and hail threat is expected through the afternoon and early
evening. Overall, the weak mid-level lapse rates and weak forcing
for ascent (mainly terrain driven) will keep the threat localized.
...New England...
As discussed in MCD #919, thunderstorms with marginal severe wind
threat are possible through the afternoon. 18Z GYX sounding sampled
modest buoyancy, but relatively high cloud bases and steep low-level
lapse rates could still contribute to occasional damaging
downbursts.
..Mosier.. 06/02/2023
.PREV DISCUSSION... /ISSUED 1056 AM CDT Fri Jun 02 2023/
...Southern High Plains...
Large-scale ascent is already underway ahead of a shortwave trough
over NM that will slowly shift into west TX through tonight. Stratus
is fairly pervasive across most of west TX, outside of the Permian
Basin. In this latter area, with mid 60s surface dew points and a
pocket of nearly full insolation, convection will likely develop in
the next couple hours. With around 8-9 C/km mid-level lapse rates
and an elongated nearly straight-line hodograph, splitting discrete
supercells are expected with very large to giant hail possible. A
couple long-lived supercells may occur as they slowly move southeast
along the Lower Pecos Valley through early evening.
More widespread thunderstorm activity is expected farther north,
initially beginning in southeast NM and then spreading into the
South Plains and southern TX Panhandle areas. Relatively larger
low-level SRH compared to farther south should support potential for
at least a couple tornadoes in addition to significant severe hail,
centered on the late afternoon period. Amalgamation of numerous
cells should result in upscale growth into an MCS by early evening
with a threat for localized significant severe wind gusts. Overall
severe threat should wane after sunset into late evening as the MCS
spreads deeper into southwest OK through the Big Country.
...Central High Plains to eastern MT...
Isolated to scattered thunderstorms will develop along a lee trough
later this afternoon in the presence of generally 50s surface dew
points. Convection will probably tend to focus near a pair of
slow-moving mid-level impulses across eastern CO and eastern MT. For
the eastern MT regime in the mid-levels, lapse rates will be weak
but compensated by a belt of 25-30 kt southeasterlies. This may be
adequate to support transient weak supercell structures. In the
eastern CO regime, steep mid-level lapse rates will counter
weaknesses in the low to mid-level hodograph. Isolated severe hail
and wind will be possible, centered on the late afternoon to early
evening.
...New England...
Isolated to scattered thunderstorms are expected downstream of a
southward-moving shortwave trough approaching from Quebec. Nearly
all enhancement to mid/upper flow will be confined to the cool side
of a surface cold front pushing south-southwest. 12Z GYX sounding
revealed very light winds throughout the troposphere. As such,
single-digit effective bulk shear is anticipated across most of the
region, with values perhaps into the teens closer to the front.
Well-mixed and inverted-v thermodynamic profiles should support
locally strong wind gusts in sporadic microbursts during the late
afternoon to early evening.
$$