342 
FXUS01 KWBC 210729
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
328 AM EDT Tue Apr 21 2026

Valid 12Z Tue Apr 21 2026 - 12Z Thu Apr 23 2026

...Pacific system will bring locally heavy rain to
northern/central California and snow to the Sierra today; heavy
snow spreads into the northern Rockies Wednesday...

...Another round of thunderstorms with heavy downpours expected
across eastern Texas today with isolated flash flooding possible...

...Gusty winds and warm, very dry conditions will lead to a
Critical Risk of fire weather along much of the High Plains
Wednesday...

A deep upper-low and associated surface frontal system will
continue to progress eastward over the western U.S. today
(Tuesday) bringing expanding shower and thunderstorm chances
across most of the West Coast and into portions of the Great
Basin. The heaviest rainfall is expected along the coastal ranges
of northern/central California and upslope regions of the Sierra
Nevada, where some isolated flooding will be possible. A period of
very heavy snow will also ramp up for the higher elevations of the
Sierra today where totals of 1-2'+ can be expected. Other ranges
of northern California, the Cascades, and into the Great Basin may
also see some snow but totals should initially remain light. The
precipitation focus will shift northward on Wednesday, continuing
for the Pacific Northwest and northern Great Basin while expanding
into the northern Rockies. Lower elevations will see rain while
snow will continue for regional ranges of the Great Basin and
spread into higher elevations of the northern Rockies, where
locally heavy snow is expected to continue through mid-week. Some
of the higher valleys in the northern Rockies may begin to see
some snow mix in by Wednesday night, though little to no
accumulations are expected.

Storm chances will also begin to ramp up across portions of the
northern/central Plains by late Wednesday as this system begins to
emerge onto the Plains. A deepening lee low/trough east of the
Rockies will also bring increasingly gusty winds along the High
Plains Wednesday. These downsloping winds will lead to warm, very
dry conditions and have prompted a broad Critical Risk of fire
weather (level 2/3) from the Storm Prediction Center. To the
south, Gulf moisture pooling along a lingering frontal boundary
and a favorably timed upper-level shortwave will bring another
round of thunderstorms to much of eastern Texas today. Locally
heavy downpours will bring a risk for some isolated instances of
flash flooding. Storm chances will continue into Wednesday but
become more scattered/less heavy as the upper-wave departs the
region and the boundary begins to dissipate. Elsewhere, a frontal
system will bring some scattered shower chances from the Great
Lakes/Ohio Valley east into the Northeast over the next couple of
days. The rest of the country should remain mostly dry. Dry,
offshore winds today through portions of west-central Florida have
also prompted a Critical Risk of fire weather.

A progressive upper-level pattern will lead to variable
temperatures across much of the country through mid-week. A strong
upper-level ridge ahead of the noted Pacific system will continue
to bring well-above average temperatures across the Interior West
east into the northern/central Plains and Midwest today.
Widespread highs in the 60s to low 80s are forecast, with some
mid- to upper-80s possible across portions of the northern/central
Plains. However, the incoming Pacific system will bring an
eastward expansion of much cooler, below average temperatures.
Highs in the 50s and 60s along the West Coast today will spread
across much of the Interior West Wednesday. A dramatic drop in
temperatures will reach portions of the northern Plains by
Thursday as highs fall into the 40s. Meanwhile, to the east,
temperatures will begin to moderate for many following a cold
front passage over the weekend. Highs will return to the 70s and
80s for the Ohio Valley/Southeast today and much of the
Mid-Atlantic as well as Texas Wednesday. Cooler temperatures will
linger longest for New England as highs remain in the 40s and 50s
through mid-week.

Putnam


Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php




$$