…Unseasonably cool temperatures continue for much of the East with frost
and freeze concerns from the Central U.S. to parts of the Mid-Atlantic and
Northeast…
…Above normal temperatures build across the central and northern High
Plains with the risk of fire weather increasing through Thursday…
…Significant pattern change begins Wednesday into Thursday across the
Pacific Northwest and Intermountain West with much colder temperatures and
the threat of widespread mountain snow…
A large area of Canadian high pressure, building southward into the
Central U.S. in the wake of yesterday’s passing cold front, will continue
to keep unseasonably cool temperatures in place across much of the eastern
half of the United States over the next few days and nights. Starting
tonight, low temperatures from the nation’s midsection to the Eastern
Seaboard will bottom out roughly 10 to 20 degrees below average for this
time of year. Low temperatures stretching from parts of Kansas all the way
to Pennsylvania are forecast to dip near or even below freezing, leading
to fairly widespread frost and freeze concerns. Those with sensitive
vegetation or other agricultural interests in these regions will want to
heed the Freeze Warnings and Frost Advisories that are currently in
effect. Despite increasing sunshine Wednesday into Thursday underneath the
bubble of high pressure, high temperatures will still struggle to climb
out of the 50s and 60s… equating to 10 to 20 degrees below average for
the middle of October.
As the large and sprawling area of high pressure moves into the Eastern
U.S. mid to late week, developing southwest flow on the backside of the
high will allow anomalously warm air to surge northward across the central
and northern High Plains. High temperatures will soar well into the 70s
and 80s on Wednesday with some places in Wyoming, Montana, and South
Dakota even having a shot at 90 degrees. This unseasonable warmth then
spreads eastward on Thursday, with high temperatures climbing 20 to 30
degrees above normal. The combination of near record warmth, low relative
humidity, gusty winds, and dry fuels will be conducive to critical fire
weather conditions across parts of the central and northern Plains on
Wednesday which may linger into Thursday.
The very warm conditions across much of the West as of late won’t last too
much longer as a significant pattern change is on the way. A strong
Pacific storm system will slam into the Pacific Northwest beginning later
Wednesday into Thursday, bringing much colder and much more seasonable
temperatures into the region behind a powerful cold front. In addition to
the colder temperatures, the storm will also bring widespread
precipitation for much of the region. While valley locations will mostly
just see rain showers, dropping snow levels will result in the first snow
of the season for many of the higher mountain elevations. Winter Storm
Watches and Warnings have already been issued for portions of the central
and northern Rockies, which go into effect late Wednesday night into
Thursday morning. If you’ll be traveling through the mountains later this
week, be sure to keep checking the forecast and be prepared for
potentially hazardous winter driving conditions.
Miller
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php
