RSS Mesoscale Discussions from Storm Prediction Center
WW 355 SEVERE TSTM MN WI 191900Z - 200100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 355
NWS Storm Prediction Center Norman OK
200 PM CDT Fri Jun 19 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central Minnesota
West Central Wisconsin
* Effective this Friday afternoon and evening from 200 PM until
800 PM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
Isolated damaging wind gusts to 65 mph possible
SUMMARY...Scattered thunderstorms are expected to intensify across
central Minnesota this afternoon and track southeastward into
western Wisconsin this evening. The strongest cells will be capable
of large hail and gusty winds.
The severe thunderstorm watch area is approximately along and 50
statute miles north and south of a line from 35 miles south
southwest of Detroit Lakes MN to 75 miles east of Minneapolis MN.
For a complete depiction of the watch see the associated watch
outline update (WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 55 knots. A
few cumulonimbi with maximum tops to 450. Mean storm motion vector
29030.
...Hart
Read more
WW 0355 Status Updates
STATUS REPORT ON WW 355
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..MEAD..06/19/26
ATTN...WFO...MPX...FGF...
STATUS REPORT FOR WS 355
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MNC003-005-009-019-025-037-041-049-053-059-065-067-085-093-095-
097-111-121-123-139-141-145-153-159-163-171-192040-
MN
. MINNESOTA COUNTIES INCLUDED ARE
ANOKA BECKER BENTON
CARVER CHISAGO DAKOTA
DOUGLAS GOODHUE HENNEPIN
ISANTI KANABEC KANDIYOHI
MCLEOD MEEKER MILLE LACS
MORRISON OTTER TAIL POPE
RAMSEY SCOTT SHERBURNE
STEARNS TODD WADENA
WASHINGTON WRIGHT
WIC005-033-091-093-095-109-192040-
WI
. WISCONSIN COUNTIES INCLUDED ARE
BARRON DUNN PEPIN
PIERCE POLK ST. CROIX
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MD 1203 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL COLORADO INTO NORTH-CENTRAL AND NORTHEAST NEW MEXICO
Mesoscale Discussion 1203
NWS Storm Prediction Center Norman OK
0243 PM CDT Fri Jun 19 2026
Areas affected...central Colorado into north-central and northeast
New Mexico
Concerning...Severe potential...Watch unlikely
Valid 191943Z - 192215Z
Probability of Watch Issuance...5 percent
SUMMARY...Isolated severe storms capable of large hail and locally
severe wind gusts appear possible this afternoon into early evening.
The limited areal coverage and magnitude of the severe-weather
threat are expected to preclude a watch issuance.
DISCUSSION...Recent trends in radar and satellite data indicate
deepening showers and thunderstorms along the Sangre De Cristo
Mountains and CO Front Range from near Las Vegas, NM to near
Colorado Springs, CO. In the short term, thunderstorms are expected
to remain in the vicinity of the high terrain owing to stronger
capping across the adjacent High Plains. However, by mid to late
afternoon, that capping is expected to weaken, allowing for a slow
southeastward drift of the storms into lower elevations. The
presence of steep, low/mid-level lapse rates and resultant MLCAPE of
around 1000 J/kg is expected to coincide with 35-40 kt of effective
bulk shear, supporting the potential for transient supercell
structures capable of isolated occurrences of large hail and perhaps
locally severe wind gusts.
The limited areal coverage and magnitude of the severe-weather
threat are expected to preclude a watch issuance.
..Mead/Hart.. 06/19/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PUB...BOU...ABQ...
LAT...LON 35530583 36020580 37160540 38760514 38980409 38430323
35900379 35060427 34910511 35120571 35530583
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
MD 1202 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL FLORIDA
Mesoscale Discussion 1202
NWS Storm Prediction Center Norman OK
0231 PM CDT Fri Jun 19 2026
Areas affected...Central Florida
Concerning...Severe potential...Watch unlikely
Valid 191931Z - 192130Z
Probability of Watch Issuance...20 percent
SUMMARY...A strong to severe downburst or two may occur across the
central Florida Peninsula this afternoon. This threat will likely
remain too isolated and transient to warrant watch issuance.
DISCUSSION...The early stages of convective development are well
underway across the central FL Peninsula amid a combination of
strong diurnal heating and weak low-level ascent along a confluence
axis draped across the state. Recent surface observations show
temperatures have warmed into the low to mid 90s with dewpoints
remaining in the mid 70s. This is supporting a regional buoyancy
maximum with MLCAPE values estimated to be around 3000 J/kg.
Additionally, low-level lapse rates are steepest (7-8 C/km) across
this region where daytime heating has been maximized. Meager
deep-layer wind shear should promote mainly short-lived cells and
loosely organized clusters, which will modulate the overall severe
threat. However, thermodynamic conditions are most favorable for
intense updrafts - as well as robust downdrafts capable of strong to
severe (45-65 mph) wind gusts - across central and eastern portions
of the state through early evening.
..Moore/Hart.. 06/19/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MFL...MLB...TBW...
LAT...LON 26598168 27318172 28108168 28518167 28658148 28688113
28588060 28368050 28038047 27578026 27158008 26868003
26558014 26328038 26218070 26178103 26238144 26398163
26598168
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
Read more
MD 1201 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN ALABAMA INTO THE FLORIDA PANHANDLE
Mesoscale Discussion 1201
NWS Storm Prediction Center Norman OK
0207 PM CDT Fri Jun 19 2026
Areas affected...Southern Alabama into the Florida Panhandle
Concerning...Severe potential...Watch unlikely
Valid 191907Z - 192100Z
Probability of Watch Issuance...5 percent
SUMMARY...Sporadic damaging winds will be possible for the next
couple of hours as a band of thunderstorms approaches the Gulf
Coast.
DISCUSSION...Over the past 1-2 hours, a band of poorly organized
convection has been drifting southward across southern AL and into
the FL Panhandle. Surface observations have largely been reporting
wind gusts between 20-30 mph with the passage of the line over the
past 30 minutes. However, GOES IR imagery has shown a trend towards
colder cloud-top temperatures associated with stronger updraft
pulses as the line propagates south into a warming air mass where
temperatures are warming into the upper 80s and low 90s. Deep-layer
wind shear remains very poor across the region and will continue to
modulate the overall severe threat; however, this trends towards
stronger updrafts and warming low-level conditions suggests the
potential for very isolated bursts of damaging winds (most likely
35-55 mph) is likely increasing. Areas downstream of the convective
bands may see sporadic damaging gusts over the next couple of hours
as the storms continue to push southward towards the coast.
..Moore/Hart.. 06/19/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TAE...MOB...
LAT...LON 30238756 30438792 30858815 31168815 31488786 31558754
31538720 31098676 30848638 30678564 30598467 30608404
30398387 30118401 29708467 29668515 29848548 30138583
30318646 30238756
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
Read more
MD 1200 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR CENTRAL MINNESOTA INTO WEST-CENTRAL WISCONSIN
Mesoscale Discussion 1200
NWS Storm Prediction Center Norman OK
0127 PM CDT Fri Jun 19 2026
Areas affected...Central Minnesota into west-central Wisconsin
Concerning...Severe potential...Watch possible
Valid 191827Z - 192100Z
Probability of Watch Issuance...60 percent
SUMMARY...The potential for severe thunderstorms capable of large
hail and damaging wind gusts is expected to increase this afternoon.
Convective trends are being monitored for a possible Severe
Thunderstorm Watch issuance.
DISCUSSION...Despite boundary-layer dewpoints only in the mid 50s to
around 60, the combination of daytime heating and cooling mid-level
temperatures are contributing to air mass destabilization with
MLCAPE expected to increase to 1000-1200 J/kg this afternoon. That
destabilization process will support the southeastward advance of
ongoing thunderstorms over the Red River Valley into the discussion
area, with additional in-situ development also possible.
Forecast soundings and the current KMPX VWP indicate strong
mid/upper-level wind fields, with long straight-line hodographs
forecast by mid to late afternoon. As such, the potential will exist
for splitting supercells capable of large hail, potentially up to
golf-ball size. There is some model signal that storms may merge
into bowing structures by late afternoon or early evening, signaling
an increase in damaging wind potential. The tendency for the
low-level wind field to veer to a westerly direction with time is
expected to limit low-level shear magnitudes and resultant tornado
potential.
Convective trends are being monitored for a possible Severe
Thunderstorm Watch issuance.
..Mead/Hart.. 06/19/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DLH...ARX...MPX...FGF...
LAT...LON 46559420 46139245 45669152 45279111 44629120 44189168
44119255 44539380 45159455 45869520 46099522 46099522
46409491 46559420
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1104 AM CDT Fri Jun 19 2026
Valid 191630Z - 201200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
MINNESOTA INTO WESTERN WISCONSIN...
...SUMMARY...
Isolated strong to severe thunderstorms may produce gusty winds
today across parts of the Upper Midwest, central Plains, from Texas
into portions of the Southeast, and across parts of the Sierra into
the northern Great Basin.
...MN/WI...
A fast moving shortwave trough over ND will track southeastward into
the upper Midwest today. 12z model guidance is in general agreement
that a pocket of modest CAPE will develop this afternoon over
central MN in a region of broken clouds and rapidly cooling
mid-level temperatures. This will likely lead to scattered
thunderstorm development, with storms tracking into western WI
before weakening this evening. Forecast soundings show steep
mid-level lapse rates and strong westerly flow aloft. Given the
strong large scale ascent, a few relatively low-topped supercells
are possible with large hail being the main risk. A small SLGT risk
has been added for this scenario.
...East TX into the Southeast...
A very moist and moderately unstable air mass is present today
across much of east TX and LA into southern MS/AL/GA and north FL.
Dewpoints in the mid-upper 70s and strong heating will lead to
MLCAPE values of over 3000 J/kg across much of this broad area.
This will lead to diurnally driven thunderstorms later today into
this evening. Steering flow and vertical shear are weak across the
region, suggesting slow-moving and rather disorganized convection.
Nevertheless, the strongest cells will pose a risk of water-loaded
downdrafts and occasionally gusty/damaging winds.
...Eastern NC...
A remnant tropical circulation is moving across NC and will be
offshore by mid-afternoon. Until then, an isolated tornado cannot
be ruled out in the stronger-sheared environment across the Outer
Banks region. Refer to MD #1197 for further details.
...KS/NE/CO/NM...
Scattered thunderstorms may develop this afternoon in a zone of
low-level warm advection over southwest NE and track into northern
KS. Steep lapse rates and sufficient shear for rotating storms
could pose a risk of large hail in the strongest cores. Other more
widely scattered convection will develop southward into eastern
CO/western KS/northeast NM, where gusty/damaging wind gusts are
possible.
...NV...
A very deeply-mixed boundary layer will develop this afternoon over
much of northern NV/northeast CA, along with enough CAPE for
high-based thunderstorms. Strong mid/high-level winds and favorable
thermodynamic profiles could result in a few storms capable of
damaging wind gusts.
..Hart/Moore.. 06/19/2026
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0258 PM CDT Fri Jun 19 2026
Valid 192000Z - 201200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
MINNESOTA AND WESTERN WISCONSIN...
...SUMMARY...
Isolated strong to severe thunderstorms may produce gusty winds
today across parts of the Upper Midwest, central Plains, from Texas
into portions of the Southeast, and across parts of the Sierra into
the northern Great Basin.
...20z Update MN/WI...
Severe potential remains evident this afternoon and evening across
the upper MS Valley. Despite modest buoyancy, anomalously strong
deep-layer flow and steep low-level lapse rates will promote
splitting supercell structures across parts of MN and WI. This will
support a risk for hail and damaging gusts with the strongest
storms. Have adjusted the 15% hail probabilities further north for
the latest radar trends. See MCD#1200 and Severe Thunderstorm Watch
#355 for additional details.
...NC/VA...
The circulation associated with remnants of former TC Arthur have
moved offshore and severe potential has decreased. Severe
probabilities were removed.
...Southeast...
A broad area of thunderstorms is ongoing along a diffuse frontal
zone from east TX across the Gulf Coast States. Occasional
downbursts remain possible with stronger multicell clusters through
this evening, given large buoyancy and the high PWAT air mass.
Vertical shear is minimal and broader storm organization is not
expected. Have adjusted the 5% wind probabilities slightly to better
capture ongoing storms. No other changes were made to the outlook.
See the prior discussion for more information.
..Lyons.. 06/19/2026
.PREV DISCUSSION... /ISSUED 1104 AM CDT Fri Jun 19 2026/
...MN/WI...
A fast moving shortwave trough over ND will track southeastward into
the upper Midwest today. 12z model guidance is in general agreement
that a pocket of modest CAPE will develop this afternoon over
central MN in a region of broken clouds and rapidly cooling
mid-level temperatures. This will likely lead to scattered
thunderstorm development, with storms tracking into western WI
before weakening this evening. Forecast soundings show steep
mid-level lapse rates and strong westerly flow aloft. Given the
strong large scale ascent, a few relatively low-topped supercells
are possible with large hail being the main risk. A small SLGT risk
has been added for this scenario.
...East TX into the Southeast...
A very moist and moderately unstable air mass is present today
across much of east TX and LA into southern MS/AL/GA and north FL.
Dewpoints in the mid-upper 70s and strong heating will lead to
MLCAPE values of over 3000 J/kg across much of this broad area.
This will lead to diurnally driven thunderstorms later today into
this evening. Steering flow and vertical shear are weak across the
region, suggesting slow-moving and rather disorganized convection.
Nevertheless, the strongest cells will pose a risk of water-loaded
downdrafts and occasionally gusty/damaging winds.
...Eastern NC...
A remnant tropical circulation is moving across NC and will be
offshore by mid-afternoon. Until then, an isolated tornado cannot
be ruled out in the stronger-sheared environment across the Outer
Banks region. Refer to MD #1197 for further details.
...KS/NE/CO/NM...
Scattered thunderstorms may develop this afternoon in a zone of
low-level warm advection over southwest NE and track into northern
KS. Steep lapse rates and sufficient shear for rotating storms
could pose a risk of large hail in the strongest cores. Other more
widely scattered convection will develop southward into eastern
CO/western KS/northeast NM, where gusty/damaging wind gusts are
possible.
...NV...
A very deeply-mixed boundary layer will develop this afternoon over
much of northern NV/northeast CA, along with enough CAPE for
high-based thunderstorms. Strong mid/high-level winds and favorable
thermodynamic profiles could result in a few storms capable of
damaging wind gusts.
Read more
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 PM CDT Fri Jun 19 2026
Valid 201200Z - 211200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE CENTRAL PLAINS...
...SUMMARY...
Severe thunderstorms are likely across portions of the central
Plains vicinity from Saturday afternoon into Saturday evening. Large
to very-large hail, severe winds (some 75+ mph), and tornadoes are
possible.
...Central Plains...
With the approach of the modest shortwave trough, a lee cyclone will
deepen through the afternoon near the Colorado/Kansas border. Mid
60s F dewpoints are possible in parts of the central High Plains
with upper 60s F dewpoints more probable into central/eastern
Kansas. Convection is expected to develop within the higher terrain
of southeast Wyoming/southwest South Dakota and within the lee
trough/cyclone by mid/late afternoon. Earlier thunderstorm
development does appear possible within weak warm advection near the
northward lifting surface boundary in central/eastern Nebraska.
40-50 kt of effective shear and steep mid-level lapse rates will
promote initial supercells capable of large/very-large hail, severe
winds, and tornadoes. The degree of tornado risk is somewhat
uncertain as there could be a relatively quick transition to linear
modes. Discrete storms that can persist into the evening would
encounter greater low-level shear as the low-level jet strengthens.
A strong tornado would be possible especially near the surface
boundary where surface winds will remain backed. QLCS circulations
will remain possible within linear modes as well. As linear/bowing
segments develop during the evening, the risk for severe wind gusts
(some 75+ mph) will increase. The southern extent and eastern extent
of the most intense activity is a bit uncertain, but some risk will
remain even into the overnight on account of the very moist airmass
and limited MLCIN.
...Northern Utah into far southeast Idaho...
Widely scattered to scattered convection is possible along the
southern fringe of the upper-level trough. Strong heating and
limited moisture will promote large temperature-dewpoint spreads at
the surface. Convection will be capable of severe wind gusts.
..Wendt.. 06/19/2026
Read more
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0233 PM CDT Fri Jun 19 2026
Valid 211200Z - 221200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
HIGH PLAINS INTO THE MID-MISSISSIPPI/LOWER OHIO VALLEYS...
...SUMMARY...
Severe storms are possible along a frontal zone from the
Mid-Mississippi Valley to the central High Plains on Sunday. Large
hail, severe winds, and tornadoes will be possible.
...Mid-Mississippi Valley...
Models indicated that convection will likely be ongoing during the
morning in portions of Missouri and will move into central/southern
Illinois. The degree of airmass recover behind this activity is not
certain. There will certainly be a corridor of greater severe
potential along the trailing outflow from central Missouri into
southern Illinois, but confidence in such a scenario remains low at
this point. Furthermore, upper-level flow is not going to be overly
strong and any supercells that can develop may struggle to maintain
intensity. Even so, the potential for large hail, severe winds, and
tornadoes is evident.
...Central High Plains...
Lingering moisture behind the weak surface front and upslope flow
during the afternoon will promote thunderstorm development within
eastern Colorado. A belt of stronger westerly flow will bring
effective shear of around 45 kt. Steep mid-level lapse rates and
long hodographs suggest potential for large to very-large (up to 2
in.) hail will be possible along with isolated severe gusts.
Activity may not move very far east given increasing MLCIN farther
into western Kansas.
...Kansas/Oklahoma/Ozarks...
Heating of a moist airmass south of the surface boundary will
promote strong buoyancy (perhaps 3000-4000 J/kg MLCAPE). As the
shortwave trough continues east, the cold front will begin to move
southward by the evening. The low-level jet will strengthen and
provide additional lift along the boundary. A line of thunderstorms
is expected to move southward. Damaging winds are the main hazard
with this activity.
...Middle Ohio Valley Vicinity...
Convection that will move through Missouri/Illinois in the morning
may continue eastward. Given the modest surface low expected to
develop, some airmass destabilization is possible into Indiana/Ohio.
Strong low-level wind fields would support a risk for damaging winds
and perhaps a tornado or two.
..Wendt.. 06/19/2026
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1053 AM CDT Fri Jun 19 2026
Valid 191700Z - 201200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF FAR NORTHERN
CALIFORNIA INTO EXTREME SOUTHERN OREGON AND NORTHWESTERN NEVADA...
No changes were made to the drawn areas. The outlook remains on
track with the latest forecast guidance. Radar returns and satellite
imagery this morning show ongoing convection over portions of the
northern CA. This activity is not expected to affect convective
initiation later in the day which will only be aided by orographic
lift over the region of highest concern. It's worth mentioning that
some forecast guidance is indicating an increase in afternoon
precipitable water values over the area of highest concern. While
there is potential for mixed wet and dry thunderstorms over locales
near the northern CA/NV border, keep in mind that these metrics are
being influenced by sub-cloud post-storm moistening before somewhat
quickly lowering below 3/4 inch once again given the progressive
storm motion. One mitigating factor for potential fire spread from
any ignitions today will be somewhat persistent cloud coverage over
the region.
..Stearns.. 06/19/2026
.PREV DISCUSSION... /ISSUED 0202 AM CDT Fri Jun 19 2026/
...Synopsis...
Broad upper troughing will overspread the Interior West as upper
ridging becomes established over the Rockies and a northwesterly
mid-level flow regime takes shape over the northern Plains to
Mid-Atlantic today. The broad upper troughing over the Interior West
will promote surface low development over the Great Basin, resulting
in dry southwesterly surface flow enveloping parts of eastern
California toward the Four Corners region. Meanwhile, deep-layer
ascent accompanying the surface low and northward mid-level moisture
transport associated with the upper trough will support thunderstorm
development across the northern Great Basin into the Pacific
Northwest through the day. The combination of dry and windy
conditions, as well as thunderstorms atop dry fuels, will support
efficient wildfire ignition/spread potential across a sizeable
portion of the Interior West today.
...Great Basin to the Four Corners...
By afternoon peak heating and ahead of the surface low, ample mixing
of a deep boundary layer up to at least 600 mb will support
widespread dry and windy conditions for several hours. From eastern
California into the Great Basin and toward the Four Corners region,
15-20 mph sustained southwesterly surface winds amid 10-15 percent
RH will overspread dry fuels, warranting Elevated highlights.
...Northern Great Basin into the Pacific Northwest...
During the afternoon, boundary-layer mixing will support increased
buoyancy amid strong deep-layer ascent, resulting in thunderstorm
development across the northern Sierra. Through the afternoon and
evening hours, these storms will gradually progress toward
southeastern Oregon into the northern Great Basin. Forecast
soundings depict inverted-v profiles approaching 500 mb with 0.75+
inch precipitable water values, suggesting that several storms will
be high-based. Fuels are receptive to wildfire spread across the
northern Great Basin into parts of the Pacific Northwest and
northern Rockies, with ERCs reaching the 80th to 90th percentiles.
As such, lightning induced ignitions are expected to be efficient
enough to warrant isolated dry thunderstorm highlights. Scattered
dry thunderstorm highlights were also included for the northern
Sierra and immediate adjacent areas, where orographic lift along the
higher terrain may support a prolonged period of greater high-based
thunderstorm coverage.
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0226 PM CDT Fri Jun 19 2026
Valid 201200Z - 211200Z
...CRITICAL FIRE WEATHER AREA FOR SCATTERED DRY THUNDERSTORMS OVER
FAR NORTHEAST NEVADA...PORTIONS OF SOUTHERN IDAHO...AND NORTHERN
UTAH...
...CRITICAL FIRE WEATHER AREA FOR DRY AND WINDY CONDITIONS OVER
SOUTHERN WYOMING...WESTERN COLORADO...EASTERN UTAH...NORTHEAST
ARIZONA...AND NORTHWEST NEW MEXICO...
An area of Scattered Dry Thunderstorms was introduced over far
northeast NV, portions of southern ID, and northern UT. The latest
forecast guidance has increased storm coverage over this area on Day
2/Saturday afternoon. While cloud bases will remain lower than
desirable for particularly dry convection, the limited precipitable
water values (generally 0.6-0.8 inch) and fast moving storm motion
(25-35 kts) will support mostly dry thunderstorms across low and mid
elevations of the drawn area. The existing Isolated Dry Thunderstorm
risk was also expanded to include additional portions of
east-central OR and southwest ID. Farther east over the higher
terrain of central ID, increased QPF shown in forecast guidance has
precluded any potential expansion over that area where lightning
activity looks to be more widespread.
The existing Critical wind/RH area was expanded northward to
encompass all of western CO and some of southern WY. The latest
forecast guidance shows that strong westerly winds (15-25 mph) will
spread northward into southern WY atop very dry dead fuels and dry
(5-15%) conditions on Day 2/Saturday afternoon.
..Stearns.. 06/19/2026
.PREV DISCUSSION... /ISSUED 0205 AM CDT Fri Jun 19 2026/
...Synopsis...
A relatively zonal mid-level flow regime will overspread the CONUS
tomorrow (Saturday), with multiple mid-level impulses poised to
traverse the zonal flow, from the Great Basin to the Mid-Mississippi
Valley. A surface cyclone will develop along the central High Plains
while a secondary surface low organizes over the Four Corners
region. Across the Great Basin into the Four Corners, dry and windy
conditions will develop during the afternoon, promoting
wildfire-spread potential. Dry/breezy conditions will also be
possible over and to the lee of the Cascades as a mid-level impulse
overspreads this region. Finally, deep-layer ascent along the
corridor of stronger mid-level zonal flow, with an accompanying
mid-level impulse, will support thunderstorm development atop dry
fuels over parts of the Pacific Northwest toward the central
Rockies.
...Portions of the Great Basin into the Four Corners Region...
By afternoon, boundary-layer mixing will support 15-20 mph
west-southwesterly surface winds amid 5-15 percent RH on a
widespread basis across much of the Great Basin into the Four
Corners. Elevated highlights have been introduced where these dry
and windy conditions will overlap with dry fuels. Furthermore,
Critical highlights were included for areas adjacent to the Four
Corners, where some guidance depict surface winds approaching 20 mph
amid near single-digit RH for several hours tomorrow afternoon.
...Portions of northern California to the central Rockies...
As a mid-level impulse tracks from the Pacific Northwest to central
Rockies, increased deep-layer ascent amid mid-level
moisture/buoyancy will support isolated high-based thunderstorm
development through the afternoon. While forecast soundings show
inverted-v profiles only extending up to 700-600 mb, stronger flow
aloft may encourage faster storm motions, decreasing precipitation
accumulations over dry fuel beds experiencing lightning strikes.
Since ERCs are expected to exceed the 80th percentile, isolated dry
thunderstorm highlights have been added for parts of far northern
California into the central Rockies, where efficient
lightning-induced ignitions are possible.
...Portions of the Pacific Northwest...
The passage of the earlier mentioned embedded mid-level impulse will
encourage dry/windy conditions atop the Cascades, along with
downslope flow along the lee of the Cascades. By afternoon peak
heating, sustained westerly surface winds may reach 15 mph (locally
higher in terrain-enhanced areas) as RH falls into the 15-20 percent
range. Given drying fuels in this region, Elevated highlights were
included.
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
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