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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 PM CDT Fri Jul 18 2025 Valid 190100Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN NE/IA TO SOUTHEAST SD AND SOUTHERN MN... ...SUMMARY... Scattered severe thunderstorms with large hail, damaging winds, and a couple of tornadoes are possible across parts of the Corn Belt in Iowa, Minnesota, Nebraska, and South Dakota tonight. ...NE/IA/SD/MN... Initial thunderstorms along the eastern SD/southwest MN are expected to greatly expand to the southwest along a quasi-stationary front into the central High Plains, as a broad low-level jet strengthens from the southern High Plains across KS. With a pronounced gradient in mid/upper-level westerlies from south to north, a complex/messy convective mode evolution is anticipated with a mix of supercells evolving into predominantly clusters and a potential MCS overnight. With a substantial MLCAPE gradient oriented north/south in southern MN to northwest-southeast across IA, the most intense storms should remain centered on the Mid-MO Valley through NE. Sufficient low-level shear amid lower 70s surface dew points will foster some tornado risk through late evening in the Mid-MO Valley vicinity. Otherwise, initial large hail threat should transition to predominantly strong/severe gusts overnight, with a gradual weakening trend towards dawn in the IA vicinity. ...Eastern NC and southeast VA... Widely scattered multicell clusters which have produced sporadic wind damage along with measured strong gusts should continue towards the coast over the next few hours. This activity should gradually subside as it encounters pockets of previously overturned air. Locally damaging winds will remain possible until these clusters sufficiently weaken. ..Grams.. 07/19/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 PM CDT Fri Jul 18 2025 Valid 190100Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN NE/IA TO SOUTHEAST SD AND SOUTHERN MN... ...SUMMARY... Scattered severe thunderstorms with large hail, damaging winds, and a couple of tornadoes are possible across parts of the Corn Belt in Iowa, Minnesota, Nebraska, and South Dakota tonight. ...NE/IA/SD/MN... Initial thunderstorms along the eastern SD/southwest MN are expected to greatly expand to the southwest along a quasi-stationary front into the central High Plains, as a broad low-level jet strengthens from the southern High Plains across KS. With a pronounced gradient in mid/upper-level westerlies from south to north, a complex/messy convective mode evolution is anticipated with a mix of supercells evolving into predominantly clusters and a potential MCS overnight. With a substantial MLCAPE gradient oriented north/south in southern MN to northwest-southeast across IA, the most intense storms should remain centered on the Mid-MO Valley through NE. Sufficient low-level shear amid lower 70s surface dew points will foster some tornado risk through late evening in the Mid-MO Valley vicinity. Otherwise, initial large hail threat should transition to predominantly strong/severe gusts overnight, with a gradual weakening trend towards dawn in the IA vicinity. ...Eastern NC and southeast VA... Widely scattered multicell clusters which have produced sporadic wind damage along with measured strong gusts should continue towards the coast over the next few hours. This activity should gradually subside as it encounters pockets of previously overturned air. Locally damaging winds will remain possible until these clusters sufficiently weaken. ..Grams.. 07/19/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 PM CDT Fri Jul 18 2025 Valid 190100Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN NE/IA TO SOUTHEAST SD AND SOUTHERN MN... ...SUMMARY... Scattered severe thunderstorms with large hail, damaging winds, and a couple of tornadoes are possible across parts of the Corn Belt in Iowa, Minnesota, Nebraska, and South Dakota tonight. ...NE/IA/SD/MN... Initial thunderstorms along the eastern SD/southwest MN are expected to greatly expand to the southwest along a quasi-stationary front into the central High Plains, as a broad low-level jet strengthens from the southern High Plains across KS. With a pronounced gradient in mid/upper-level westerlies from south to north, a complex/messy convective mode evolution is anticipated with a mix of supercells evolving into predominantly clusters and a potential MCS overnight. With a substantial MLCAPE gradient oriented north/south in southern MN to northwest-southeast across IA, the most intense storms should remain centered on the Mid-MO Valley through NE. Sufficient low-level shear amid lower 70s surface dew points will foster some tornado risk through late evening in the Mid-MO Valley vicinity. Otherwise, initial large hail threat should transition to predominantly strong/severe gusts overnight, with a gradual weakening trend towards dawn in the IA vicinity. ...Eastern NC and southeast VA... Widely scattered multicell clusters which have produced sporadic wind damage along with measured strong gusts should continue towards the coast over the next few hours. This activity should gradually subside as it encounters pockets of previously overturned air. Locally damaging winds will remain possible until these clusters sufficiently weaken. ..Grams.. 07/19/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 PM CDT Fri Jul 18 2025 Valid 190100Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN NE/IA TO SOUTHEAST SD AND SOUTHERN MN... ...SUMMARY... Scattered severe thunderstorms with large hail, damaging winds, and a couple of tornadoes are possible across parts of the Corn Belt in Iowa, Minnesota, Nebraska, and South Dakota tonight. ...NE/IA/SD/MN... Initial thunderstorms along the eastern SD/southwest MN are expected to greatly expand to the southwest along a quasi-stationary front into the central High Plains, as a broad low-level jet strengthens from the southern High Plains across KS. With a pronounced gradient in mid/upper-level westerlies from south to north, a complex/messy convective mode evolution is anticipated with a mix of supercells evolving into predominantly clusters and a potential MCS overnight. With a substantial MLCAPE gradient oriented north/south in southern MN to northwest-southeast across IA, the most intense storms should remain centered on the Mid-MO Valley through NE. Sufficient low-level shear amid lower 70s surface dew points will foster some tornado risk through late evening in the Mid-MO Valley vicinity. Otherwise, initial large hail threat should transition to predominantly strong/severe gusts overnight, with a gradual weakening trend towards dawn in the IA vicinity. ...Eastern NC and southeast VA... Widely scattered multicell clusters which have produced sporadic wind damage along with measured strong gusts should continue towards the coast over the next few hours. This activity should gradually subside as it encounters pockets of previously overturned air. Locally damaging winds will remain possible until these clusters sufficiently weaken. ..Grams.. 07/19/2025 Read more

MD 1712 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR EASTERN SOUTH DAKOTA...SOUTHWEST MINNESOTA
Mesoscale Discussion 1712 NWS Storm Prediction Center Norman OK 0603 PM CDT Fri Jul 18 2025 Areas affected...Eastern South Dakota...southwest Minnesota Concerning...Severe potential...Watch possible Valid 182303Z - 190100Z Probability of Watch Issuance...60 percent SUMMARY...Initial supercells will be capable of large hail, severe winds, and perhaps a tornado or two. Timing of widely scattered to scattered storm development is not clear, but should occur within the next few hours. Eventual upscale growth will lead to a greater wind threat with time. A watch is possible as convective trends warrant. DISCUSSION...Cloud cover has remained across eastern South Dakota this afternoon. This has hindered surface heating and several models are not handling this very well. Several CAM solutions from earlier today depicted storms would already be ongoing. Recent HRRR/RRFS runs suggest a more reasonable, later start. With a storm now having developed in northeast South Dakota, a gradual increase in storm coverage is probable over the next few hours. The 18Z OAX sounding showed a capping layer near 800 mb which likely extends northward to some extent. A subtle increase in mid-level ascent and a modest low-level jet this evening are the likely forcing mechanisms to help erode the modest capping. Given effective shear of 40-50 kts and MLCAPE of 1500-2000 J/kg, initial supercells will be capable of large hail and severe wind gusts. The increase in 850 mb flow this evening will enlarge low-level hodographs, but the overall tornado threat is less clear given the less than ideal low-level thermodyamic profiles. Convection is then expected to grow upscale by mid/late evening. Severe wind gusts would be the primary hazard after this occurs. ..Wendt/Hart.. 07/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...FSD...ABR... LAT...LON 43859803 44189886 44349885 44639833 45309716 45519637 45219550 44849479 44759469 44599467 44049491 43729546 43519637 43589736 43859803 MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

MD 1713 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHEAST VA INTO NORTHEAST NC
Mesoscale Discussion 1713 NWS Storm Prediction Center Norman OK 0609 PM CDT Fri Jul 18 2025 Areas affected...Parts of southeast VA into northeast NC Concerning...Severe potential...Watch unlikely Valid 182309Z - 190045Z Probability of Watch Issuance...20 percent SUMMARY...Localized damaging wind remains possible early this evening. DISCUSSION...Multiple clusters of strong thunderstorms are ongoing early this evening across southeast VA into northeast NC. The environment across the region remains modestly favorable for organized convection, with rich low-level moisture, MLCAPE of 2000-3000 J/kg, and veering wind profiles resulting in effective shear of 20-30 kt. However, storm intensity and longevity have been somewhat limited thus far, potentially due to weak low-level flow and poor midlevel lapse rates. A storm cluster moving across south-central/southeast VA has gradually become better organized early this evening, and may remain capable of producing at least isolated wind damage as it moves eastward. Additional discrete cells developing ahead of this cluster have also intensified somewhat, and may merge into the larger cluster with time. These discrete cells may exhibit transient supercell characteristics in the presence of multiple surface boundaries, and be capable of producing localized wind damage and perhaps some hail. Other storm clusters are ongoing across parts of central into northeast NC. Deep-layer shear is somewhat weaker with southward extent, but these clusters will remain capable of producing localized wind damage before weakening later this evening. ..Dean/Hart.. 07/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...RNK... LAT...LON 35147732 35537917 37397851 37517708 37377632 36587588 35807562 35207721 35147732 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

A state of emergency was declared at the San Carlos Apache Tribe reservation due to drought. Cattle were dying from an absence of grass and water, so ranchers were hauling water, hay and nutrients to the livestock. Wells were being drilled to access more water. Acorn and pine trees were stressed by drought also. 12News (Phoenix, Ariz.), July 18, 2025

MD 1711 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF CENTRAL/EASTERN KS
Mesoscale Discussion 1711 NWS Storm Prediction Center Norman OK 0517 PM CDT Fri Jul 18 2025 Areas affected...Parts of central/eastern KS Concerning...Severe potential...Watch unlikely Valid 182217Z - 190015Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong to severe gusts and hail are possible into early evening. DISCUSSION...A small storm cluster that developed near the OK/KS border is propagating northeastward along an expanding outflow late this afternoon, with additional storm initiation noted into parts of east-central KS. A weak MCV is moving across the region, and may help to sustain scattered thunderstorms through the early evening. Storms approaching Wichita have a history of producing golf-ball sized hail and localized severe gusts. While deep-layer flow is relatively weak, modest veering with height is supporting effective shear of 20-30 kt, sufficient for at least transient storm organization in the presence of strong buoyancy (MLCAPE of greater than 3000 J/kg). The most likely hazard into early evening may be strong to severe gusts along the northeastward-moving outflow across south-central KS, and also with localized downbursts associated with the more discrete storms. However, isolated hail cannot be ruled out given the magnitude of buoyancy. ..Dean/Hart.. 07/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TOP...ICT... LAT...LON 37299812 38279837 39239763 39529700 39509623 39199596 38699591 37859649 37459685 37299732 37299812 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

000
ABNT20 KNHC 182334
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Fri Jul 18 2025

For the North Atlantic...Caribbean Sea and the Gulf of America:

Central Tropical Atlantic:
A tropical wave interacting with a broad area of low pressure is
producing disorganized showers and thunderstorms more than 800 miles
southwest of the Cabo Verde Islands. Environmental conditions could
become marginally conducive for gradual development late this
weekend through early next week as the system moves westward to
west-northwestward around 10 mph. By the middle of next week,
environmental conditions are forecast to become unfavorable for
further development.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Hagen

000
ABPZ20 KNHC 182336
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Fri Jul 18 2025

For the eastern and central North Pacific east of 180 longitude:

Well Southwest of the Baja California Peninsula:
A large area of disorganized showers and thunderstorms associated
with a tropical wave is located well southwest of the Baja
California peninsula. Some gradual development of this system is
possible during the next few days while it moves west-northwestward
at 10 to 15 mph. By the early to middle part of next week,
environmental conditions are expected to become unfavorable for
further development.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Jelsema

000
ABNT20 KNHC 182334
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Fri Jul 18 2025

For the North Atlantic...Caribbean Sea and the Gulf of America:

Central Tropical Atlantic:
A tropical wave interacting with a broad area of low pressure is
producing disorganized showers and thunderstorms more than 800 miles
southwest of the Cabo Verde Islands. Environmental conditions could
become marginally conducive for gradual development late this
weekend through early next week as the system moves westward to
west-northwestward around 10 mph. By the middle of next week,
environmental conditions are forecast to become unfavorable for
further development.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Hagen

No watches are valid as of Fri Jul 18 23:12:02 UTC 2025.

MD 1712 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR EASTERN SOUTH DAKOTA...SOUTHWEST MINNESOTA
Mesoscale Discussion 1712 NWS Storm Prediction Center Norman OK 0603 PM CDT Fri Jul 18 2025 Areas affected...Eastern South Dakota...southwest Minnesota Concerning...Severe potential...Watch possible Valid 182303Z - 190100Z Probability of Watch Issuance...60 percent SUMMARY...Initial supercells will be capable of large hail, severe winds, and perhaps a tornado or two. Timing of widely scattered to scattered storm development is not clear, but should occur within the next few hours. Eventual upscale growth will lead to a greater wind threat with time. A watch is possible as convective trends warrant. DISCUSSION...Cloud cover has remained across eastern South Dakota this afternoon. This has hindered surface heating and several models are not handling this very well. Several CAM solutions from earlier today depicted storms would already be ongoing. Recent HRRR/RRFS runs suggest a more reasonable, later start. With a storm now having developed in northeast South Dakota, a gradual increase in storm coverage is probable over the next few hours. The 18Z OAX sounding showed a capping layer near 800 mb which likely extends northward to some extent. A subtle increase in mid-level ascent and a modest low-level jet this evening are the likely forcing mechanisms to help erode the modest capping. Given effective shear of 40-50 kts and MLCAPE of 1500-2000 J/kg, initial supercells will be capable of large hail and severe wind gusts. The increase in 850 mb flow this evening will enlarge low-level hodographs, but the overall tornado threat is less clear given the less than ideal low-level thermodyamic profiles. Convection is then expected to grow upscale by mid/late evening. Severe wind gusts would be the primary hazard after this occurs. ..Wendt/Hart.. 07/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...FSD...ABR... LAT...LON 43859803 44189886 44349885 44639833 45309716 45519637 45219550 44849479 44759469 44599467 44049491 43729546 43519637 43589736 43859803 MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

MD 1713 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHEAST VA INTO NORTHEAST NC
Mesoscale Discussion 1713 NWS Storm Prediction Center Norman OK 0609 PM CDT Fri Jul 18 2025 Areas affected...Parts of southeast VA into northeast NC Concerning...Severe potential...Watch unlikely Valid 182309Z - 190045Z Probability of Watch Issuance...20 percent SUMMARY...Localized damaging wind remains possible early this evening. DISCUSSION...Multiple clusters of strong thunderstorms are ongoing early this evening across southeast VA into northeast NC. The environment across the region remains modestly favorable for organized convection, with rich low-level moisture, MLCAPE of 2000-3000 J/kg, and veering wind profiles resulting in effective shear of 20-30 kt. However, storm intensity and longevity have been somewhat limited thus far, potentially due to weak low-level flow and poor midlevel lapse rates. A storm cluster moving across south-central/southeast VA has gradually become better organized early this evening, and may remain capable of producing at least isolated wind damage as it moves eastward. Additional discrete cells developing ahead of this cluster have also intensified somewhat, and may merge into the larger cluster with time. These discrete cells may exhibit transient supercell characteristics in the presence of multiple surface boundaries, and be capable of producing localized wind damage and perhaps some hail. Other storm clusters are ongoing across parts of central into northeast NC. Deep-layer shear is somewhat weaker with southward extent, but these clusters will remain capable of producing localized wind damage before weakening later this evening. ..Dean/Hart.. 07/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...RNK... LAT...LON 35147732 35537917 37397851 37517708 37377632 36587588 35807562 35207721 35147732 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

MD 1711 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF CENTRAL/EASTERN KS
Mesoscale Discussion 1711 NWS Storm Prediction Center Norman OK 0517 PM CDT Fri Jul 18 2025 Areas affected...Parts of central/eastern KS Concerning...Severe potential...Watch unlikely Valid 182217Z - 190015Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong to severe gusts and hail are possible into early evening. DISCUSSION...A small storm cluster that developed near the OK/KS border is propagating northeastward along an expanding outflow late this afternoon, with additional storm initiation noted into parts of east-central KS. A weak MCV is moving across the region, and may help to sustain scattered thunderstorms through the early evening. Storms approaching Wichita have a history of producing golf-ball sized hail and localized severe gusts. While deep-layer flow is relatively weak, modest veering with height is supporting effective shear of 20-30 kt, sufficient for at least transient storm organization in the presence of strong buoyancy (MLCAPE of greater than 3000 J/kg). The most likely hazard into early evening may be strong to severe gusts along the northeastward-moving outflow across south-central KS, and also with localized downbursts associated with the more discrete storms. However, isolated hail cannot be ruled out given the magnitude of buoyancy. ..Dean/Hart.. 07/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TOP...ICT... LAT...LON 37299812 38279837 39239763 39529700 39509623 39199596 38699591 37859649 37459685 37299732 37299812 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

MD 1710 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF CENTRAL/EASTERN WYOMING...FAR SOUTHWEST SOUTH DAKOTA...NEBRASKA PANHANDLE
Mesoscale Discussion 1710 NWS Storm Prediction Center Norman OK 0507 PM CDT Fri Jul 18 2025 Areas affected...Parts of central/eastern Wyoming...far southwest South Dakota...Nebraska Panhandle Concerning...Severe potential...Watch unlikely Valid 182207Z - 190000Z Probability of Watch Issuance...20 percent SUMMARY...Isolated supercells will pose some risk of large hail and isolated severe wind gusts. A watch is not anticipated. DISCUSSION...Heating of a modestly moist airmass up against the terrain with aid from a subtle shortwave trough in the northern Great Basin has promoted isolated supercell development from central into eastern Wyoming. As storms move eastward late this afternoon, they will encounter greater surface moisture, particularly the activity in east-central Wyoming. Effective shear of 30-40 kts and steep mid-level lapse rates will favor large hail production. Isolated severe winds are also possible given the steep low-level lapse rates and somewhat dry boundary layer. MLCIN does increase into the adjacent Plains. The spatial extent of severe activity will likely be limited by this factor. ..Wendt.. 07/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...UNR...CYS...RIW... LAT...LON 42050503 43310714 43640771 43760828 43910889 43970895 44270897 44490864 44570767 44310628 44150478 43060298 42490287 41900308 41700338 42050503 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

No Mesoscale Discussions are in effect as of Fri Jul 18 21:12:02 UTC 2025.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0341 PM CDT Fri Jul 18 2025 Valid 201200Z - 261200Z A mid/upper-level tough is forecast to deepen across the Pacific Northwest Day 3/Sunday into Day 4/Monday. Thereafter, the evolution of the trough is somewhat uncertain, largely due to inter/intra-model variability. Though, many recent solutions now suggest some form of splitting with a portion of the trough ejecting across the northern Rockies and another becoming cutoff (or redeveloping) off/near the coast of California/Oregon through the remainder of the week. ...Day 3/Sunday - Day 5/Tuesday: Wind/RH... Increasing mid-level winds - associated with the aforementioned trough - will promote a broadening area of dry/breezy southwesterly flow Day 3/Sunday across portions of the northern Great Basin, far northeastern California, southeastern Oregon, and southwest Montana. At this time, locally critical conditions appear most likely across wind-prone areas of the Snake River Plain in Idaho. Fire weather conditions are forecast to shift a bit southward while also increasing in coverage and intensity Day 4/Monday, as the aforementioned trough continues to deepen. While an area of critical fire weather conditions appears probable, relatively poor run-to-run model consistency precludes increasing critical probabilities to 70% at this time. Dry/breezy conditions are forecast to linger into Day 5/Tuesday across the Great Basin. Though, relaxing mid-level winds and reduced surface pressure gradients should promote lighter surface winds and locally elevated fire weather conditions. ...Day 4/Monday - Day 5/Tuesday: Dry Thunderstorms... Isolated dry thunderstorms are possible Day 4/Monday into Day 5/Tuesday across portions of northern Great Basin, Northwest, and northern Rockies, as increasing moisture associated with the aforementioned trough impinges on the area. While forecast guidance suggests precipitable water values may be relatively high (0.8 - 1+ inch), somewhat fast-moving storm motions and critically receptive fuels suggest a mix of wet/dry modes. At this time, uncertainty remains too large to introduce probabilities for dry thunderstorms. ..Elliott.. 07/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0341 PM CDT Fri Jul 18 2025 Valid 201200Z - 261200Z A mid/upper-level tough is forecast to deepen across the Pacific Northwest Day 3/Sunday into Day 4/Monday. Thereafter, the evolution of the trough is somewhat uncertain, largely due to inter/intra-model variability. Though, many recent solutions now suggest some form of splitting with a portion of the trough ejecting across the northern Rockies and another becoming cutoff (or redeveloping) off/near the coast of California/Oregon through the remainder of the week. ...Day 3/Sunday - Day 5/Tuesday: Wind/RH... Increasing mid-level winds - associated with the aforementioned trough - will promote a broadening area of dry/breezy southwesterly flow Day 3/Sunday across portions of the northern Great Basin, far northeastern California, southeastern Oregon, and southwest Montana. At this time, locally critical conditions appear most likely across wind-prone areas of the Snake River Plain in Idaho. Fire weather conditions are forecast to shift a bit southward while also increasing in coverage and intensity Day 4/Monday, as the aforementioned trough continues to deepen. While an area of critical fire weather conditions appears probable, relatively poor run-to-run model consistency precludes increasing critical probabilities to 70% at this time. Dry/breezy conditions are forecast to linger into Day 5/Tuesday across the Great Basin. Though, relaxing mid-level winds and reduced surface pressure gradients should promote lighter surface winds and locally elevated fire weather conditions. ...Day 4/Monday - Day 5/Tuesday: Dry Thunderstorms... Isolated dry thunderstorms are possible Day 4/Monday into Day 5/Tuesday across portions of northern Great Basin, Northwest, and northern Rockies, as increasing moisture associated with the aforementioned trough impinges on the area. While forecast guidance suggests precipitable water values may be relatively high (0.8 - 1+ inch), somewhat fast-moving storm motions and critically receptive fuels suggest a mix of wet/dry modes. At this time, uncertainty remains too large to introduce probabilities for dry thunderstorms. ..Elliott.. 07/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more