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FNUS21 KWNS 010638

FWDDY1



Day 1 Fire Weather Outlook  

NWS Storm Prediction Center Norman OK

0138 AM CDT Thu Apr 01 2021



Valid 011200Z - 021200Z



...CRITICAL FIRE WEATHER AREA FOR NORTHERN MONTANA...NORTH

DAKOTA...AND FAR NORTHWEST MINNESOTA...

...CRITICAL FIRE WEATHER AREA FOR THE GREATER WESTERN OKLAHOMA

PANHANDLE REGION...



...Synopsis...

Early morning water-vapor reveals an upper-level ridge building over

the western CONUS as a trough and attendant surface cold front begin

to push off the East Coast. The passage of this cold front across

the Plains and into the Southeast over the past 48 hours has yielded

very dry conditions across much of the central U.S., which will help

support another day of fire weather concerns from the southern to

northern U.S. borders. 



...Northern Plains...

Dewpoint values in the single digits and teens are noted from

eastern MT into the central Plains, and regional 00 UTC soundings

reveal minimal boundary-layer moisture. Mostly clear to partly

cloudy skies this afternoon will help support another day of

humidity values in the 20-30% range. A weak upper-level shortwave is

noted in water-vapor imagery propagating northeastward towards the

apex of the synoptic ridge. Stronger flow associated with this

feature, along with weak synoptic lift ahead of the wave, will

support the deepening of a lee low over the Canadian Prairies. In

response, south to southwesterly winds are forecast to increase into

the 15-20 mph range from central NE into SD and will likely reach

the 20-25 mph range for ND and northern MT. A broad swath of

elevated conditions are expected, and a few areas of critical

conditions appear likely - particularly across northern MT where

downslope warming/drying will aid in RH reductions and across

central ND, which is immediately downstream from the driest air mass

(per regional soundings). 10-hour fuel moisture in the 5-10% range

across the region will support the fire weather threat given the

expected meteorological conditions. 



...Southern High Plains...

Lee troughing along the High Plains juxtaposed next to surface high

over the Midwest/MS Valley region will lead to strengthening

pressure-gradient winds this afternoon for the southern High Plains.

Southerly winds at 15-25 mph will be common, and although downslope

affects will be minimal, a antecedent dry air mass and mostly clear

skies will help RH values fall into the low teens this afternoon.

The most likely location for critical conditions resides across the

greater OK Panhandle region where fuels are receptive and the

potential for sustained critical wind/RH is highest (largely due to

strengthening low to mid-level flow through the day). To the

southeast into the TX Panhandle, elevated to critical fire weather

conditions are possible, but slightly more marginal fuels preclude

an expansion at this time. 



...Southern Arizona into Southern New Mexico...

Guidance continues to show reasonably high agreement in the

potential for elevated fire weather conditions this afternoon from

the southern NM/AZ border into west-central AZ. Easterly winds up to

15-20 mph should be common and will likely coincide with RH values

in the teens to perhaps single digits. Fuels across this region

become more marginal with northern extent, but the coverage of cured

fuels should be sufficient to support an elevated fire weather

concern for much of the area. 



...Coastal South California...

North to northeasterly winds will likely continue into the early

morning hours over coastal south CA due to residual surface high

pressure to the north and an approaching shortwave trough to the

south. A handful of surface observations from the region show

elevated to critical conditions ongoing, which may persist into the

mid-morning hours before winds diminish as the low moves onshore.

Despite the ongoing wind/RH conditions, fuels remain only modestly

receptive and approaching rain showers and weak thunderstorms may

further limit fuel readiness. Consequently, no highlights are

introduced.



..Moore.. 04/01/2021



...Please see www.spc.noaa.gov/fire for graphic product...



$$