SPC - No watches are valid as of Thu Aug 14 19:43:02 UTC 2025

No watches are valid as of Thu Aug 14 19:43:02 UTC 2025.

SPC MD 1945

MD 1945 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF EXTREME NORTHEAST NEVADA INTO CENTRAL AND NORTHERN UTAH...SOUTHEASTERN IDAHO...AND SOUTHWESTERN INTO CENTRAL WYOMING

Mesoscale Discussion 1945
NWS Storm Prediction Center Norman OK
0240 PM CDT Thu Aug 14 2025

Areas affected...portions of extreme northeast Nevada into central
and northern Utah...southeastern Idaho...and southwestern into
central Wyoming

Concerning...Severe potential...Watch unlikely 

Valid 141940Z - 142215Z

Probability of Watch Issuance...20 percent

SUMMARY...Thunderstorms will pose a risk for strong to potentially
severe wind gusts through the afternoon and early evening hours.

DISCUSSION...High-based thunderstorms are developing atop a dry
boundary layer, where 40-50 T/Td spreads are already in place. RAP
forecast soundings, and the DPG 18Z observed sounding, all depict
inverted-v profiles extending up to 500 mb, with 20-40 kts of
southwesterly flow constrained to the buoyant/cloud-bearing layer.
Given 0-3 km lapse rates already exceeding 9 C/km in spots,
conditions are favorable for fast-moving thunderstorms capable of
producing dry downbursts, with strong erratic wind gusts possible. A
few of these gusts may exceed 50 kts. However, the overall severe
risk should remain widely scattered at best, so a Severe
Thunderstorm Watch issuance is not currently anticipated.

..Squitieri/Mosier.. 08/14/2025

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...CYS...RIW...GJT...SLC...PIH...BOI...LKN...

LAT...LON   41061505 42221408 43101190 43390988 42780847 42030786
            41330795 40800836 40350875 39760983 39301126 39071219
            39101288 39331355 39541411 39781450 40131495 41061505 

MOST PROBABLE PEAK WIND GUST...55-70 MPH

SPC MD 1944

MD 1944 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHWEST TO CENTRAL MN

Mesoscale Discussion 1944
NWS Storm Prediction Center Norman OK
0237 PM CDT Thu Aug 14 2025

Areas affected...southwest to central MN

Concerning...Severe potential...Watch unlikely 

Valid 141937Z - 142130Z

Probability of Watch Issuance...20 percent

SUMMARY...A marginal severe threat might develop before early
evening within a few cells shifting slowly east from southwest
Minnesota. A Severe Thunderstorm Watch issuance is unlikely.

DISCUSSION...Along the backside of a remnant MCV moving from
south-central to southeast MN, lower-level warm theta-e advection
has persisted across southwest MN. A belt of 40-45 kt
southwesterlies has been consistently sampled by the FSD VWP from
1-3 km and this is expected to gradually shift east into this
evening. RAP-based forecast soundings and observed cloud bases
suggest initial cells are probably rooted around 750 mb along the
differential heating zone west of the MCV cloud shield. Nearly all
guidance has lacked robust convective signal this afternoon, except
for the 12Z HRW-NSSL. It has a low-probability scenario of a
supercell developing within this regime and tracking south-southeast
along the differential heating corridor. The more probable scenario
is for sporadic attempts at transient updraft rotation, capable of
producing marginally severe hail and locally strong gusts. These
threats should remain within a confined corridor at any one time,
but gradually translate east into early evening.

..Grams/Mosier.. 08/14/2025

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...MPX...FSD...

LAT...LON   45379593 45769549 45779492 45519447 45129408 44699388
            44189377 43739422 43759513 44189589 44759625 45379593 

MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN

SPC Aug 14, 2025 1630 UTC Day 1 Convective Outlook

SPC 1630Z Day 1 Outlook
      
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1129 AM CDT Thu Aug 14 2025

Valid 141630Z - 151200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA...

...SUMMARY...
Thunderstorms capable of producing large hail and severe wind gusts
may occur this afternoon into tonight across parts of the
northern/central Plains and upper Mississippi Valley. Isolated
strong to severe gusts are also possible from the eastern Great
Basin into the central Rockies.

...Northern Plains into the Upper MS Valley...
Recent surface analysis places a low over northwest ND, along a cold
front arcing from west-central Manitoba into south-central MT. A
surface trough also extends southward from this low to another weak
low in southeast CO. Ample low-level moisture exists across the
Plains east of this surface troughing, with mid 60s dewpoints
extending up through central and eastern ND. Moist southerly
low-level flow is forecast to persist throughout the day. This
low-level moisture advection combined with evapotranspiration and
low-level convergence near the front is expected to result in upper
60s to perhaps low 70s dewpoints ahead of the front across the
eastern Dakotas by early evening. Cooling mid-level temperatures are
expected across the region, which will combine with the abundant
low-level moisture to support strong to very strong buoyancy by the
late afternoon/early evening. Recent guidance suggests MLCAPE will
range from 3000 to 4000 J/kg across the eastern Dakotas, western MN,
and central/eastern NE by 00Z Friday. 

Despite this robust buoyancy, warm low to mid-level temperatures and
related capping introduce uncertainty regarding convective
initiation, particularly with southward extent. Greatest potential
for convective initiation remains across eastern ND where glancing
large-scale ascent attendant to the substantial shortwave trough
moving through Saskatchewan will augment low-level convergence along
the southeastward-progressing cold front. 

Any convection which can be sustained could pose a threat for large
to isolated very large hail given a favorable thermodynamic and
kinematic environment. Given the warm and dry low to mid-levels,
strong downdrafts are possible as well. Upscale growth into clusters
along the front is possible, and some damaging gusts could occur
with these storms as well. Inhibition will quickly increase with
eastward extent across MN as nocturnal cooling of the boundary layer
occurs, limiting the eastward extent of the severe threat.

Additionally, the low-level jet will likely weaken throughout the
day but then strengthen again later this evening from western KS
into western IA. Associated warm-air advection could result in
isolated elevated convection across central MN. Most of these storms
should be sub-severe, but a few instances of hail are possible.

...Central High Plains/Central Plains...
Scattered high-based thunderstorms should develop across the central
Rockies this afternoon before the spreading eastward/southeastward
into the central High Plains. A deeply mixed boundary layer and high
cloud bases will support strong gusts with this activity as it moves
across central High Plains. As this convection spreads eastward and
encounters greater instability along/east of a surface lee trough,
it may reintensify, with the potential for 
severe gusts continuing into central NE. The lack of stronger
forcing aloft and modest deep-layer shear should temper the overall
severe threat with southward extent.

...Eastern Great Basin into central Rockies...
The shortwave trough currently moving into central CA will continue
eastward/southeastward throughout the day. Lift associated with this
wave will interact with the modest mid-level moisture across the
Great Basin to support scattered thunderstorm development. High
cloud bases and a deeply mixed boundary layer could support strong
downdrafts within the strongest storms, particularly across northern
UT where the best overlap between forcing, buoyancy, and modest
southwesterly flow aloft exists.

..Mosier/Squitieri.. 08/14/2025


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SPC Aug 14, 2025 1730 UTC Day 2 Convective Outlook

SPC 1730Z Day 2 Outlook
      
Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1231 PM CDT Thu Aug 14 2025

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
WISCONSIN AND FAR EASTERN MINNESOTA...

...SUMMARY...
Scattered severe storms are likely over parts of the northern Plains
and Upper Mississippi Valley on Friday.

...Synopsis...
A belt of stronger mid-level flow will be present across the
northern Plains on Friday along the northern periphery of a broad
mid-level ridge. Within this flow, a weak mid-level shortwave trough
(perhaps amplified by Day1/Thursday convection across the central
Rockies) will move across the northern Plains and into the Upper
Midwest. This feature may be a focus for severe storms on Friday
afternoon/evening. Another weak mid-level shortwave trough is
forecast to traverse the central Rockies with associated ascent
overspreading the central/northern High Plains. At the surface, weak
lee troughing will be present across the central/northern High
Plains with a front extending northeast across the northern Plains
and into the Upper Midwest. 

...Upper Midwest...
Moderate to strong instability is forecast to develop south of a
stationary front across the Upper Midwest Friday afternoon. The
combination of ascent associated with a passing weak mid-level
shortwave trough and strengthening isentropic ascent as the
low-level jet strengthens, may provide ample lift for scattered
thunderstorms Friday afternoon/evening. Several CAMS are in
relatively good agreement for convective initiation across eastern
Minnesota with the potential for upscale growth into a MCS across
Wisconsin late Friday evening. Have introduced a Slight Risk across
this region for an initial large hail threat, followed by an
increasing severe wind threat if storms grow upscale. However, this
area may need to be moved or enlarged in later outlooks due to the
inherent lack of predictability within a low-amplitude pattern. Some
of this unpredictability can be seen by relative outliers (HRRR and
MPAS) which seems to stem from difference in convective evolution on
Day 1/Thursday across the central Rockies and adjacent Plains
tonight. 

...Central/Northern High Plains into the northern Plains...
Another weak mid-level shortwave trough is expected to traverse the
Rockies on Friday and eventually overspread the northern Plains by
Friday evening. Moderate to strong instability and moderate shear
along the southern periphery of the stronger mid-level westerlies
may result severe storms. Large hail would be possible in the
initial, cellular stages (isolated severe wind across the NE
Panhandle where a hot/well-mixed environment will be present),
before an increasing severe wind threat may develop by later in the
evening across South Dakota. If this MCS can maintain itself far
enough east during the evening, the strengthening low-level jet
across central and eastern South Dakota could maintain this MCS with
some isolated severe wind threat into the early morning hours on
Saturday across eastern South Dakota and perhaps far western
Minnesota and northwest Iowa.

..Bentley.. 08/14/2025


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SPC Aug 14, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

SPC 1930Z Day 3 Outlook
      
Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0227 PM CDT Thu Aug 14 2025

Valid 161200Z - 171200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
CENTRAL/NORTHERN PLAINS TO LOWER MICHIGAN...

...SUMMARY...
Isolated to scattered strong to severe storms are possible Saturday
from the central/northern Plains to Lower Michigan.

...Discussion...
Thunderstorms may be ongoing Saturday morning along a frontal zone
from the northern Plains to the western Great Lakes. The location
and strength of this morning convection will have significant
impacts on more focused zones of severe weather threat on Saturday.
A MCS may be ongoing across Wisconsin/northern Illinois/western
Michigan on Saturday morning. This MCS or a remnant MCV in its wake,
may provide a focus for severe storms across Lower Michigan Saturday
afternoon. In addition, a MCS may be ongoing across eastern South
Dakota and southwest Minnesota on the nose of the low-level jet. If
the environment downstream of this MCS can destabilize during the
morning, a severe weather threat may materialize as this MCS moves
east along the front. If neither of these solutions occur, the
severe weather threat may be somewhat more isolated. However, very
strong to extreme instability is expected along the frontal zone
with sufficient shear for some storm organization.  

Strong heating in the Plains may result in a few isolated high-based
storms from central Nebraska to western South Dakota and potentially
into far southwest Montana with a primary severe wind threat during
the afternoon/early evening.

Convection is expected along most of the frontal zone from eastern
South Dakota to Michigan Saturday night as the low-level jet
strengthens and height falls overspread the region. Isolated large
hail is possible from these storms.

..Bentley.. 08/14/2025


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SPC Day 1 Fire Weather Outlook

SPC Day 1 Fire Weather Outlook
          
Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1148 AM CDT Thu Aug 14 2025

Valid 141700Z - 151200Z

...CRITICAL FIRE WEATHER AREA FOR SCATTERED DRY THUNDERSTORMS ACROSS
PORTIONS OF THE NORTHEASTERN GREAT BASIN...

Minor updates were made to extend Isolated Dry Thunderstorm chances
into portions of the Sierra Nevada in southern California in
alignment with trends in guidance. The Scattered Dry Thunderstorm
area across northeastern Nevada into northern Utah, southern Idaho,
and western Wyoming remains unchanged. Highest confidence in the
best coverage of thunderstorms remains across this region.

The Elevated delineations across the Snake River Plain and portions
of the Great Basin also remain unchanged. Across the Great Basin,
south to southwesterly winds will overlap afternoon relative
humidity reductions to 10-15%. Winds in the Snake River Plain will
be more west to southwesterly, with relative humidity reductions to
10-15%. Gusty and erratic winds will be possible near thunderstorms.
See previous discussion below.

..Thornton.. 08/14/2025

.PREV DISCUSSION... /ISSUED 1252 AM CDT Thu Aug 14 2025/

...Synopsis...
Dry thunderstorms will be the primary fire weather concern for today
across the northeastern Great Basin, though warm, dry, and windy
conditions will likely develop across parts of the Great Basin and
northern Rockies. A slight uptick in fire activity over the past 24
hours across the Great Basin and northern Rockies confirms that
receptive fuels remain in place across much of the region.

...Dry Thunderstorms...
Early-morning water-vapor imagery depicts a plume of mid-level
moisture across the Great Basin ahead of a migratory upper trough
moving into CA. This moisture plume supported isolated dry
thunderstorms yesterday across the region, and will similarly foster
100-500 J/kg MUCAPE from central NV northeastward into portions of
ID, WY, UT, and CO. Regional 00z soundings and recent GOES imagery
are sampling PWAT values between 0.3 to 0.6 inch, which when
combined with very dry boundary-layer conditions, will support dry
thunderstorms. A combination of ascent ahead of the approaching
wave, modest lift within the right-entrance region of a departing
upper jet, and orographic ascent will support isolated thunderstorms
across a broad swath of the region. Latest CAM guidance continues to
show the potential for several smaller corridors of concentrated
thunderstorms. Where exactly these corridors will emerge through the
afternoon remains somewhat uncertain, but the general consensus is
that areas of higher thunderstorm coverage are likely. The Isolated
dry thunderstorm risk area has been expanded to capture the
reasonable envelope of dry thunderstorm potential with receptive
fuels. Similarly, the Scattered dry thunderstorm risk area was
adjusted to highlight the most probable corridors of greater
thunderstorm coverage.

...Hot/Dry/Windy...
Very dry conditions will prevail across the Great Basin region with
another day of RH minimums in the single digits to low teens.
Surface pressure falls ahead of the approaching trough will promote
breezy conditions with sustained winds around 15 mph across much of
the eastern Great Basin into far western Colorado. Portions of the
Snake River Plain in eastern ID, as well as the eastern slopes of
the Bitterroot Mountains will see similar wind speeds within a
modest downslope flow regime. Gusts between 20-25 mph will support
transient critical fire weather conditions across both regions.

...Please see www.spc.noaa.gov/fire for graphic product...


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