Fire Weather Outlook Discussion
Issued by NWS
Issued by NWS
949 FNUS28 KWNS 202117 FWDD38 Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... $$