Fire Weather Outlook
— Day 3-8
Synopsis
An upper-level ridge is likely to amplify over the central U.S. keeping troughing entrenched across the northwestern U.S. Hot, dry conditions well persist under the ridge over portions of the southern/central Plains. Farther west, a series of short waves rounding the base of the broader upper trough over the Northwest will introduce a period of cooler/wetter conditions to much of the Pacific Northwest and northern Rockies through the end of the week. Several days of cooler temperatures, cloud cover and accumulating rainfall should reduce overall fire weather concerns. A corridor of drier southwest flow southeast of the trough will present fire weather concerns where drier fuels exist across portions of WY/southern MT on Day 3/Wednesday, with lingering concerns in central WY Day 4/Thursday.
Parts of Wyoming and southern Montana
A zone of stronger mid-level winds between the trough over the Northwest and ridging across the central U.S. will promote a fire weather concern to parts of central/eastern WY and adjacent southern MT on Day 3/Wednesday. Fuels remain receptive across eastern WY as evidenced from ERCs percentiles in the 80-90th percentile range. This persistent deep layer southwest flow in the presence of lee surface troughing in central/northern High Plains will support southwest surface winds of 15-20 mph amid RH as low as 10% in favorable downslope areas. Rainfall prior to onset of dry and breezy conditions is expected to be minimal allowing fuels to remain dry. 40% Critical probabilities were extended northward into southern MT on Day 3/Wednesday with minimal changes on Day 4/Thursday. Longer term ensemble guidance suggests a continuation of this dry southwest flow pattern into Day 5/Friday, where 40% Critical probabilities have been introduced for parts of northeastern WY.
Great Basin
Similarly, robust southwest winds of 15-25 mph and low daytime RH are likely within a swath from southern NV into western UT on Day 3-5/Wednesday-Friday. However, recent rainfall has muted fuel receptivity in this area, with no critical probabilities introduced for this outlook.
000 FNUS28 KWNS 312136 FWDD38 Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0434 PM CDT Mon Aug 31 2026 Valid 021200Z - 081200Z ...Synopsis... An upper-level ridge is likely to amplify over the central U.S. keeping troughing entrenched across the northwestern U.S. Hot, dry conditions well persist under the ridge over portions of the southern/central Plains. Farther west, a series of short waves rounding the base of the broader upper trough over the Northwest will introduce a period of cooler/wetter conditions to much of the Pacific Northwest and northern Rockies through the end of the week. Several days of cooler temperatures, cloud cover and accumulating rainfall should reduce overall fire weather concerns. A corridor of drier southwest flow southeast of the trough will present fire weather concerns where drier fuels exist across portions of WY/southern MT on Day 3/Wednesday, with lingering concerns in central WY Day 4/Thursday. ...Parts of Wyoming and southern Montana... A zone of stronger mid-level winds between the trough over the Northwest and ridging across the central U.S. will promote a fire weather concern to parts of central/eastern WY and adjacent southern MT on Day 3/Wednesday. Fuels remain receptive across eastern WY as evidenced from ERCs percentiles in the 80-90th percentile range. This persistent deep layer southwest flow in the presence of lee surface troughing in central/northern High Plains will support southwest surface winds of 15-20 mph amid RH as low as 10% in favorable downslope areas. Rainfall prior to onset of dry and breezy conditions is expected to be minimal allowing fuels to remain dry. 40% Critical probabilities were extended northward into southern MT on Day 3/Wednesday with minimal changes on Day 4/Thursday. Longer term ensemble guidance suggests a continuation of this dry southwest flow pattern into Day 5/Friday, where 40% Critical probabilities have been introduced for parts of northeastern WY. ...Great Basin... Similarly, robust southwest winds of 15-25 mph and low daytime RH are likely within a swath from southern NV into western UT on Day 3-5/Wednesday-Friday. However, recent rainfall has muted fuel receptivity in this area, with no critical probabilities introduced for this outlook. ..Williams.. 08/31/2026 ...Please see www.spc.noaa.gov/fire for graphic product... $$