Fire Weather Outlook Discussion
Issued by NWS
Issued by NWS
759 FNUS28 KWNS 132202 FWDD38 Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Thu Aug 13 2026 Valid 151200Z - 211200Z ...Synopsis... The extended forecast period begins with mid-level troughing in place over the west CONUS coast and broad ridging in place over the eastern two-thirds of the CONUS. By Day 4/Sunday, ridging builds back westward over much of the Intermountain West. By Day 5/Monday, models begin to diverge, though the general consensus is for a shortwave trough to progress through the flow and impinge on the northern CA coast that afternoon. However, differences in the amplitude of this small disturbance will result in some uncertainty as to the sensible surface weather as it passes overhead. By the time Day 6/Tuesday arrives, larger uncertainties amongst forecast guidance are presented with a mid-level trough strengthening near the Pacific Northwest. On Day 7/Wednesday and Day 8/Thursday, a more significant mid-level trough is expected to move onshore and progress across the northwestern quadrant of the CONUS. However, significant differences remain between forecast guidance as to the amplitude and speed of this system as it moves eastward. ...Day 3/Saturday through Day 5/Monday... The aforementioned shortwave trough will provide lift amid sufficient instability to generate probabilities of isolated morning and afternoon thunderstorms over portions of central OR on Day 3/Saturday. Precluding this threat are the two days of preceding thunderstorm activity on Day 1/Thursday and Day 2/Friday. Thus, additional probabilities may be needed in future outlook cycles if storms trend drier and/or less-than-forecast precipitation is received leading up to Day 3/Saturday. Additional chances for thunderstorms are possible again on Day 4/Sunday and Day 5/Monday over northern CA and southern/central OR. While the likelihood of thunderstorm occurrence is currently low and uncertain due to the nature of the aforementioned pattern evolution, so is the preceding precipitation accumulation, particularly across portions of central OR. ...Day 6/Tuesday through Day 7/Wednesday... There are initial signs of coincident dry and windy conditions over portions of western/northern Great Basin on Day 6/Tuesday and Day 7/Wednesday. Should the slower end of the forecast guidance spectrum come to fruition regarding the progression of the aforementioned mid-level trough early next week, the pattern would support a tightening surface pressure gradient amid above-normal temperatures, promoting deep-mixing and gusty southerly flow from central CA through far southwestern MT for at least a day if not two depending on the resilience of the ridge centered over the southern High Plains. ..Stearns.. 08/13/2026 ...Please see www.spc.noaa.gov/fire for graphic product... $$