Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
359 PM EDT Sat Apr 15 2023

Valid 00Z Sun Apr 16 2023 - 00Z Tue Apr 18 2023

...Showers and thunderstorms move from the Mississippi Valley to the East
Coast Sunday-Monday...

...Accumulating snowfall forecast for portions of the Upper Midwest
starting Sunday evening...

...Temperatures drop for the Great Lakes/Northeast Monday after an
anomalously warm week while the Plains sees a warm up...

...Series of Pacific storm systems brings unsettled weather to the Pacific
Northwest/Northern Rockies...

Shower and thunderstorm chances will continue for portions of the
Mid-Atlantic/Northeast Saturday evening as a surface wave moves through
the region. More widespread showers and thunderstorms will also push
eastward along a cold front from the Mississippi Valley to the East Coast
through the day Sunday and lingering into Monday. A deepening upper-level
low will help to enhance precipitation totals across portions of the Great
Lakes Sunday, leading to a Marginal Risk of Excessive rainfall (level
1/4). Melting snow in addition to locally heavy rainfall may lead to a few
isolated instances of flooding. Cold air will push southward over the
Upper Midwest on the backside of the low as moisture continues to flow in
from the southeast. Accumulating snow totals between 4-7 inches, with
locally higher amounts possible, are forecast later Sunday-Monday for
portions of northern Wisconsin and the Upper Peninsula of Michigan where
Winter Storm Watches are in effect. Gusty winds may lead to areas of
blowing snow. Some locally heavy rainfall is also possible for the urban
corridor of South Florida ahead of the cold front Sunday, with isolated
flash flooding remaining a concern given the recent historic rainfall.

Highs will remain well above average Sunday for the Great Lakes/Northeast
with temperatures in the 60s, 70s, and even some low 80s for eastern
portions of the Great Lakes and the Interior Northeast. Highs will soar
into the mid-80s for portions of the Mid-Atlantic. Onshore flow will keep
temperatures cooler and in the 50s and 60s for coastal portions of the
northern Mid-Atlantic and New England. However, in addition to the
precipitation chances, the cold front will bring big changes
temperature-wise Monday. Highs will only get into the 50s, 60s, and low
70s for the Northeast, much closer to average but quite the change after
numerous record highs were set the past few days. Temperatures will be
even more sharply cooler for the Great Lakes, with highs in the 30s and
40s for the Mississippi Valley Sunday spreading across the Great Lakes
Monday. Meanwhile, it will be a chilly start to the day across the Plains
Sunday morning with below freezing temperatures as far south as the Texas
Panhandle, where Freeze Warnings are in effect for sensitive new spring
vegetation. High temperatures will rebound a bit into the 50s for the
Northern Plains, 60s for the Central Plains, and 70s for the Southern
Plains outside of far south Texas. On Monday, however, a ridge will start
to build in overhead as the upper-level low moving towards the Great Lakes
departs, sending temperatures above average and into the 60s for the
Northern High Plains, 70s for the Central Plains, and 80s for the Southern
Plains.

Embedded upper-level energy rotating around a closed low over the
Northeast Pacific will bring enhanced Pacific moisture and unsettled
weather to the Pacific Northwest and Northern Rockies the next couple of
days. Lower elevation coastal/valley rain and higher elevation mountain
snow will spread inland over the Pacific Northwest Sunday as an initial
cold front moves inland. Enhanced moisture/precipitation will spread
eastward into the Northern Rockies by late Sunday evening as another front
moves into the Pacific Northwest early Monday, keeping precipitation
chances up across the region. Some moderate snow accumulations are
forecast for higher elevations of the northern Sierra and Rockies, with
locally heavier accumulations possible for the Cascades and northern
Coastal Ranges of California. Cooler, below average temperatures will
spread inland following the series of cold fronts, with highs in the low
50s Sunday for the Pacific Northwest expanding into northern California,
the northern Great Basin, and the Northern Rockies Monday. Highs will be a
bit above average for the rest of the West, with 60s and 70s for the Great
Basin and Central/Southern Rockies and 80s to low 90s for the Desert
Southwest.

Putnam


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