No watches are valid as of Sun Aug 2 20:18:01 UTC 2026.MD 1823 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHEASTERN ARIZONA AND FAR SOUTHWEST NEW MEXICO
Mesoscale Discussion 1823
NWS Storm Prediction Center Norman OK
0316 PM CDT Sun Aug 02 2026
Areas affected...portions of southeastern Arizona and far southwest
New Mexico
Concerning...Severe potential...Watch unlikely
Valid 022016Z - 022215Z
Probability of Watch Issuance...20 percent
SUMMARY...High-based thunderstorms are expected to increase in
coverage over the higher terrain before spreading southwestward into
the lower deserts this afternoon and evening. Isolated strong to
severe gusts are possible.
DISCUSSION...As of 2015 UTC, regional visible imagery showed initial
thunderstorms were developing over the southern Mogollon Rim and
higher terrain across southeastern AZ and far southwest NM. A very
warm air mass is in place with temperatures in the 90ss to 100s F
with very steep lapse rates also present. Despite only modest
surface moisture (dewpoints in the 50s F) the air mass should
continue to destabilize with further heating and orographic ascent
this afternoon. This should allow for scattered thunderstorms late
this afternoon and into the evening.
Beneath the upper ridge over the West, flow aloft is fairly light,
but ~20-25 kts of deep-layer shear will support occasional
organization of multicell clusters as outflow consolidates and
storms move southwestward off the higher terrain. The steep
low-level lapse rates and clustering could support isolated strong
to severe gusts with the more robust storms. However, the weak
buoyancy and limited vertical shear suggest organization and severe
potential will be largely sporadic. Thus, a WW appears unlikely.
..Lyons/Mosier.. 08/02/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ABQ...EPZ...TWC...FGZ...PSR...
LAT...LON 31641233 33131181 33461113 33801064 33980939 33640892
33020860 32420863 31780875 31170902 31130958 31211072
31281102 31641233
MOST PROBABLE PEAK WIND GUST...55-70 MPH
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1116 AM CDT Sun Aug 02 2026
Valid 021630Z - 031200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE EAST
AS WELL AS PARTS OF THE SOUTHWEST AND NORTHERN PLAINS...
...SUMMARY...
Scattered strong to locally severe thunderstorm development is
expected this afternoon and evening across parts of the lower Great
Lakes and upper Ohio Valley into the middle and southern Atlantic
Piedmont. Damaging winds are the primary hazard, although a tornado
could occur.
...Eastern States...
Current satellite imagery shows a positively titled shortwave trough
extending from Lower MI southwestward into the Mid-South, while
recent surface analysis places a corridor of low pressure associated
with this shortwave from the Middle OH Valley into the Lower Great
Lakes. Several surface lows are embedded within this broader area of
low pressure, including a primary low over north-central OH/western
Lake Erie. A cold front extends southward from this low to the TN/NC
border vicinity before arcing back more southwestward through
central AL and southern MS.
This system (i.e. both the shortwave trough and associated cold
front) is forecast to gradually push eastward while weakening.
Airmass preceding this system is very moist, evidenced by upper
60s/low 70s dewpoints and PW values at or above 2 inches on the
regional 12Z soundings. Widespread cloud cover is in place, but
ample moisture has already resulted in airmass destabilization,
although the overall buoyancy will remain muted by poor lapse rates.
General expectation is for thunderstorm coverage to increase
substantially over the next few hours, fostered by a combination of
low-level confluence and modest large-scale ascent.
Low to mid-level flow throughout the eastern periphery of the
shortwave trough is generally expected to be modest, ranging from
around 40 kt across the Allegheny Plateau/upper Ohio Valley/lower
Great Lakes vicinity to 20 kt across GA and SC. Consequently, a few
more organized storms are possible across portions of the Allegheny
Plateau, upper Ohio Valley, and lower Great Lakes, while a largely
disorganized multicellular mode is anticipated elsewhere.
Water-loaded downbursts are the primary risk, although low-level
shear/SRH in the presence of a moist boundary layer suggests a brief
tornado is possible where greater storm organization is
expected.
...North Dakota/northwest Minnesota...
Expansive upper ridging exists from southern CA/western AZ through
the Plains and into Manitoba and Ontario. A strong shortwave trough
is forecast to progress through Canadian Prairie Provinces within
the northern periphery of this ridging. A cold front associated with
this wave is expected to push eastward across the Dakotas,
interacting with a moistening airmass across the region. A
conditional risk for severe thunderstorms exists this afternoon, but
most of the guidance keeps the airmass capped and free of deep
convection. Better potential for thunderstorm development is
expected overnight and into tomorrow morning as large-scale ascent
attendant to the approaching shortwave combines with warm-air
advection to foster elevated thunderstorm development. Isolated
instances of hail and a strong gust or two are possible with these
storms.
...Southeast Arizona/far southwest New Mexico...
Widely scattered thunderstorms should develop over the
mountains/higher terrain of the central/southern Arizona/New Mexico
border vicinity this afternoon. Moderate easterly/northeasterly
mid-level flow should favor southwestward motion into the lower
terrain of southeast Arizona. Modest buoyancy should allow for storm
persistence across southeast AZ, including the potential for
isolated strong to severe gusts.
..Mosier/Lyons.. 08/02/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Sun Aug 02 2026
Valid 022000Z - 031200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE EAST
AS WELL AS PARTS OF THE SOUTHWEST AND NORTHERN PLAINS...
...SUMMARY...
Scattered strong to locally severe thunderstorm development is
expected this afternoon and evening across parts of the lower Great
Lakes and upper Ohio Valley into the middle and southern Atlantic
Piedmont. Damaging winds are the primary hazard, although a tornado
could occur.
...20Z Update...
Only minor changes were made with this update. The MRGL Risk was
expanded slightly eastward in portions of eastern SC, where an
ongoing cluster of thunderstorms will continue to pose a risk of
damaging wind gusts, given a very warm/moist downstream air mass.
Farther north, the MRGL Risk was expanded into parts of northern NJ
and northeast PA. Clouds breaks have supported modest
destabilization of a moist air mass, and high-resolution guidance
depicts thunderstorms moving into the area tonight -- focused along
a northward-moving warm front. Despite modest instability, enhanced
low-level flow/shear overspreading the region in tandem with the
warm front could support a couple loosely organized cells/clusters
with an accompanying risk of damaging wind gusts and perhaps a brief
tornado. Elsewhere, the forecast remains on track and no changes
were needed.
..Weinman.. 08/02/2026
.PREV DISCUSSION... /ISSUED 1116 AM CDT Sun Aug 02 2026/
...Eastern States...
Current satellite imagery shows a positively titled shortwave trough
extending from Lower MI southwestward into the Mid-South, while
recent surface analysis places a corridor of low pressure associated
with this shortwave from the Middle OH Valley into the Lower Great
Lakes. Several surface lows are embedded within this broader area of
low pressure, including a primary low over north-central OH/western
Lake Erie. A cold front extends southward from this low to the TN/NC
border vicinity before arcing back more southwestward through
central AL and southern MS.
This system (i.e. both the shortwave trough and associated cold
front) is forecast to gradually push eastward while weakening.
Airmass preceding this system is very moist, evidenced by upper
60s/low 70s dewpoints and PW values at or above 2 inches on the
regional 12Z soundings. Widespread cloud cover is in place, but
ample moisture has already resulted in airmass destabilization,
although the overall buoyancy will remain muted by poor lapse rates.
General expectation is for thunderstorm coverage to increase
substantially over the next few hours, fostered by a combination of
low-level confluence and modest large-scale ascent.
Low to mid-level flow throughout the eastern periphery of the
shortwave trough is generally expected to be modest, ranging from
around 40 kt across the Allegheny Plateau/upper Ohio Valley/lower
Great Lakes vicinity to 20 kt across GA and SC. Consequently, a few
more organized storms are possible across portions of the Allegheny
Plateau, upper Ohio Valley, and lower Great Lakes, while a largely
disorganized multicellular mode is anticipated elsewhere.
Water-loaded downbursts are the primary risk, although low-level
shear/SRH in the presence of a moist boundary layer suggests a brief
tornado is possible where greater storm organization is
expected.
...North Dakota/northwest Minnesota...
Expansive upper ridging exists from southern CA/western AZ through
the Plains and into Manitoba and Ontario. A strong shortwave trough
is forecast to progress through Canadian Prairie Provinces within
the northern periphery of this ridging. A cold front associated with
this wave is expected to push eastward across the Dakotas,
interacting with a moistening airmass across the region. A
conditional risk for severe thunderstorms exists this afternoon, but
most of the guidance keeps the airmass capped and free of deep
convection. Better potential for thunderstorm development is
expected overnight and into tomorrow morning as large-scale ascent
attendant to the approaching shortwave combines with warm-air
advection to foster elevated thunderstorm development. Isolated
instances of hail and a strong gust or two are possible with these
storms.
...Southeast Arizona/far southwest New Mexico...
Widely scattered thunderstorms should develop over the
mountains/higher terrain of the central/southern Arizona/New Mexico
border vicinity this afternoon. Moderate easterly/northeasterly
mid-level flow should favor southwestward motion into the lower
terrain of southeast Arizona. Modest buoyancy should allow for storm
persistence across southeast AZ, including the potential for
isolated strong to severe gusts.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1224 PM CDT Sun Aug 02 2026
Valid 031200Z - 041200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN
NORTH DAKOTA...NORTHWEST MINNESOTA...AND A SMALL PART OF NORTHEAST
SOUTH DAKOTA......
...SUMMARY...
Widely scattered to scattered severe storms are expected across
eastern North Dakota, northwest Minnesota, and a small part of
northeast South Dakota Monday afternoon into evening. Severe wind
gusts and large hail will be the primary hazards. Isolated damaging
winds are possible from central and eastern South Dakota into
western Nebraska, in portions of the Mid-Atlantic into New England,
and southeast Arizona.
...Synopsis...
A progressive mid-level trough will move across the Northern Rockies
into the Northern Plains and upper Midwest Monday, with a belt of
unseasonably strong west to southwesterly flow overspreading
portions of the Dakotas into northern/central Minnesota. At the
surface, a cold front will shift eastward from the northern to the
central Plains, with a surface low moving across the Dakotas and a
secondary low across eastern Colorado.
Across the Northeast, a second mid-level trough will bring enhanced
southwesterly mid-level flow across the region. At the surface, a
warm front will lift northward across portions of New England with a
cold front advancing south and eastward as a surface low tracks into
Quebec.
...Northern and central Plains into the upper Mississippi Valley...
Elevated convection is likely to be ongoing at the start of the
period Monday morning across North Dakota into northern Minnesota.
These will pose some potential for large hail. Preceding morning
convection, steepening low to mid-level lapse rates along with
moistening with the strong southerly low-level jet should allow for
moderate to strong instability to redevelop by the afternoon.
Renewed thunderstorm development is expected along and ahead of the
cold front. Supercell wind profiles will be in place. Initially,
forecast soundings indicate lingering capping at the base of the
EML. This may erode through time but relatively warm 750-800 mb
levels may lead to fairly high LCLs, which may inhibit tornado
potential though large clockwise curved hodographs will be common.
The primary threats are expected to be large hail and damaging wind.
Capping at the base of an EML may remain further south, limiting
convection with southern extent into South Dakota and Nebraska.
Nonetheless, CAM guidance suggests signal for a few isolated
supercells to develop further south with potential for large hail
and damaging wind.
...New England into the Mid-Atlantic...
Widely scattered thunderstorm activity is expected to be ongoing
across the Mid-Atlantic and New England through much of the period.
Pockets of more focused daytime heating may result in moderate
instability by the afternoon. Aided by forcing for ascent attendant
to the short-wave trough, thunderstorms are expected to increase in
coverage and intensity through the afternoon along and ahead of the
front, namely in areas that experience greater air mass
destabilization. Steepening low-level lapse rates and the presence
of 35-45 kt of deep-layer shear may support embedded bowing segments
capable of damaging wind gusts.
...Southeast Arizona...
Easterly flow will favor thunderstorm development across the high
terrain in Southeast Arizona Monday. Widely scattered activity will
build across the high terrain and move into the lower valleys
through the afternoon and evening. A well mixed boundary layer,
moderate instability, and modest shear around 20-25 kts will support
potential for an organized cluster or two with potential to produce
damaging winds.
..Thornton.. 08/02/2026
|
