Elevated |
Critical |
Extreme |
Iso DryT |
Scattered DryT |
805 FNUS21 KWNS 230604 FWDDY1 Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0104 AM CDT Mon Jun 23 2025 Valid 231200Z - 241200Z ...Synopsis... Elevated fire weather concerns will persist across the greater southern Great Basin and Four Corners region today as breezy conditions continue within a dry air mass. Low to mid-level flow over the Intermountain West is expect to weaken over the next 24 hours as a leading shortwave impulse ejects northward into the Canadian Prairies. A secondary, weaker shortwave will settle into the lower CO Valley through today, which will maintain southwesterly flow across the southern Great Basin and into the Four Corners region. Diurnal heating of a very dry air mass (as sampled by regional 00z RAOBs) will promote wind gusts between 20-35 mph by late afternoon, though ensemble guidance continues to suggest that sustained winds will most likely remain between 15-20 mph for most locations. Regardless, increasing rainfall deficits and antecedent dry fuels/ongoing fires will support another day of at least low-end fire weather concerns as dry/breezy conditions become more prevalent through the afternoon. ..Moore.. 06/23/2025 ...Please see www.spc.noaa.gov/fire for graphic product... $$
916 FNUS22 KWNS 231959 FWDDY2 Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Mon Jun 23 2025 Valid 241200Z - 251200Z ...Southern Great Basin/Four Corners region... Stronger mid-level flow ahead of an upper-level trough will remain over the greater Four Corners region. Efficient daytime boundary later mixing will continue to promote a corridor of breezy southwest winds amid afternoon relative humidity of 10-15 percent to promote Elevated fire weather conditions from northern Arizona, southeastern Arizona into southern Wyoming. ...Northern Nevada... Some convection aided by higher terrain is expected across northern Nevada Tuesday afternoon. Limited instability/moisture profiles along with marginal fuel dryness (ERC values in the 80-85 percentile range) should limit ignition efficiency of slow moving isolated showers and thunderstorms across the area. ..Williams.. 06/23/2025 .PREV DISCUSSION... /ISSUED 0111 AM CDT Mon Jun 23 2025/ ...Synopsis... Another day of elevated fire weather conditions is expected for parts of the intermountain West on Tuesday. An upper trough currently settling into the southern Great Basin/lower CO River Valley is expected to stall and slowly de-amplify over the next 48 hours. This will maintain a belt of modest mid-level flow over parts of the eastern Great Basin/western Four Corners region. Although pressure gradient winds will generally be in the mid/upper teens, diurnal heating and deep mixing of a dry air mass will promote frequent gusts between 20-35 mph across the region - especially from northern AZ into eastern UT and southern WY under a belt of somewhat stronger 700-500 mb flow. Afternoon RH minimums in the low to mid teens are expected, and coupled with dry fuels, will help support another day of elevated fire weather conditions (though transient periods of critical conditions are anticipated where stronger gusts can occur). ...Dry Thunderstorms... Isolated thunderstorms appear possible Tuesday afternoon across portions of northeastern Nevada under the upper-level low. Cold temperatures aloft combined with modest mid-level moisture and strong low-level heating will support thermodynamic profiles adequate for weak convection, but perhaps limited precipitation. Given dry fuels across the region, some dry-thunderstorm risk is expected. The primary limiting factor to a more substantial dry-thunderstorm concern is slow storm motions (less than 10 knots), which should increase the probability of wetting rainfall under the convective cores. ...Please see www.spc.noaa.gov/fire for graphic product... $$
657 FNUS28 KWNS 232157 FWDD38 Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0455 PM CDT Mon Jun 23 2025 Valid 251200Z - 011200Z ...Synopsis... A deamplifying upper-level trough over the Great Basin and diminishing mid-level flow will usher in lighter winds for the Four Corners region and Southwest for Day 3/Wednesday. An upper-level trough will gradually translate eastward along the Northern Tier from the Pacific Northwest on Day 5/Thursday into the Great Lakes by Day 8/Monday. An amplifying ridge across the Intermountain West early next week will promote lighter surface winds but well above normal temperatures for much of the Western U.S. ...Day 3/Wednesday... Enhanced downslope winds and drying aided by accelerating mid-level flow ahead of an upper-level trough is expected across northeastern California/northwestern Nevada Wednesday. However, fuels remain marginal in terms of spread potential precluding critical probabilities at this time. ...Day 4-7/Thursday-Sunday... With active wave pattern farther north, muted mid and upper-level flow and weak surface pressure gradients will promote lighter, mainly terrain driven winds across much of the Intermountain West and Southwest late this week, into early next week. ...Day 8/Monday... Long term ensemble guidance indicates another upper-level trough encroaching upon the Pacific Coast Day 8/Monday, potentially ushering in fire weather concerns across the Great Basin (dry and breezy ahead of the trough) as well as dry lightning potential across the Oregon Cascades. Considerable uncertainty exists in the magnitude of moisture ahead of the trough, precluding introduction of dry thunderstorm probabilities in the long term. ..Williams.. 06/23/2025 ...Please see www.spc.noaa.gov/fire for graphic product... $$