776
FXUS21 KWNC 161746
PMDTHR
US Hazards Outlook
NWS Climate Prediction Center College Park MD
300 PM EDT May 16 2025

SYNOPSIS: Multiple ensemble means indicate weaker mid-level high pressure
across the West compared to yesterday, with this feature shifted further east
and over the High Plains at the beginning of week-2. This translates to only
slight risks of excessive heat lingering across portions of the southwestern
Contiguous U.S. and Texas. Episodes of high winds are possible across coastal
California and portions of Texas and southeastern New Mexico. Warm temperatures
combined with dry conditions and gusty winds may elevate wildfire risk across
parts of Texas.

HAZARDS

Slight risk of excessive heat for parts of the Southwest, Central Great Basin,
and the Southern Plains, Sat-Mon, May 24-26.

Slight risk of episodic high winds for parts of California, Sat-Tue, May 24-27.

Slight risk of episodic high winds for portions of Texas and southeastern New
Mexico, Sat-Mon, May 24-26.

DETAILED SUMMARY

FOR MONDAY MAY 19 - FRIDAY MAY 23:
https://www.wpc.ncep.noaa.gov/threats/threats.php

FOR SATURDAY MAY 24 - FRIDAY MAY 30: Compared to yesterday, multiple model
means indicate a weaker mid-level ridge across the Interior West and shifted
eastward, centered over the High Plains by the beginning of week-2. This
translates to decreasing excessive heat signals during this period compared to
yesterday. A slight risk of excessive heat is highlighted across parts of the
Southwest, Central Great Basin, and the Southern Plains, May 24-26, where the
Probabilistic Extremes Tools (PETs) indicate at least a 20% chance of exceeding
the 85th percentile climatologically. Maximum temperatures range from
potentially exceeding 90 deg F across the Central Great Basin to greater than
100 deg F across the Desert Southwest. PETs indicate temperatures exceeding 95
deg F across eastern portions of Texas, however, enhanced dewpoints across the
region could result in heat index values exceeding triple digits. Additionally,
calibrated heat tools show increased chances based on the GEFS (ECENS) indicate
chances greater than 50% (20%) of heat index values exceeding the 90th
percentile, resulting in this region being included in the heat risk.



Predicted thermal surface low pressure over Baja California and southern
California combined with adjacent surface high pressure off the coast of
California is anticipated to lead to a tight pressure gradient along the coast.
Therefore, a slight risk of episodic high winds is posted for the coast of
California, May 24-27. There is good agreement among the GEFS and ECENS PETs
indicating at least a 20% chance of wind speeds exceeding the 85th percentile
and 25 mph across this region.



Surface low pressure is anticipated to remain fairly stationary across eastern
New Mexico extending southward into western Texas. This feature may support
enhanced wind speeds in the region, supporting a slight risk of episodic high
winds across Texas and southeastern New Mexico, May 24-26. Hot temperatures
combined with dry conditions and gusty winds increases the risk of wildfires in
the region. Additionally, there is increased chances for dry
thunderstorms/lightning in this area where a dryline is anticipated, which
could initiate wildfire activity.



Subtropical ridging across the southeastern CONUS may promote enhanced onshore
flow into the Mississippi Valley, bringing enhanced precipitation and isolated
thunderstorms to portions of the Middle and Lower Mississippi Valley,
especially during the middle of week-2. Daily rainfall totals are not
anticipated to reach hazardous criteria, thus an associated precipitation
hazard is not designated. Any enhanced rainfall, however, could increase the
risk for localized flooding across parts of the Ozarks and Middle Mississippi
Valley.



No hazards are issued over Alaska. Warmer than normal springtime temperatures
are favored for much of the Mainlande, with a tilt towards above-normal
precipitation for  the Mainland and Southeast, but nothing approaching
hazardous thresholds.

FORECASTER: Melissa Ou

$$