Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
334 PM EST Tue Feb 01 2022
Valid 12Z Fri Feb 04 2022 - 12Z Tue Feb 08 2022
...Lingering Snow/Ice Threat exits the Mid-Atlantic/Northeast
Friday...
...Overview...
A positively tilted and reinforced mean trough aloft should hold
strong across much of the CONUS through the medium range period
(Friday-Tuesday), as strong upper riding builds over both the
western Atlantic and the eastern Pacific (and periodically
extending into parts of the west). On Friday, a shortwave moving
through the Northeast will drive a potent cold front off the East
coast, with potentially heavy wintry precip likely coming to an
end on the north side of this system. Into this weekend,
uncertainty begins to increase over details of additional
shortwaves dropping down the east side of the ridge in the West as
well as a series of northern stream shortwaves which should
support a train of northern tier waves into early next week. Upper
troughing into the East early next week may induce wintry coastal
waves, with some signal for additional development of any in a
series of lows.
...Guidance Evaluation/Predictability Assessment...
Models and ensembles provide a reasonably similar larger scale
pattern evolution through medium range time scales, but present
significant run to run variance with smaller scale embedded upper
impulses and surface wave reflections and local QPF focus. Prefer
a composite of the otherwise decently clustered solutions of the
GFS/ECMWF/UKMET/Canadian models for days 3/4 (Fri/Sat) before
transitioning to the still compatible GEFS/ECMWF ensemble means by
days 6/7 to minimize the less predictable forecast components.
This provides a good forecast basis along with the 13 UTC National
Blend of Models and WPC continuity.
...Weather Highlights/Threats...
Troughing into the East on Friday and a leading wavy cold front
through the East will continue the threat for lingering
significant snow/ice from the Mid-Atlantic to especially southern
New England. Lingering moderate to locally heavy showers are still
possible across parts of the Southeast along the trailing front
Friday with periodic additional activity through the weekend into
early next week with additional frontal waves/upper impulses.
Elsewhere, northern tier systems may produce secondary shots of
cold air into the central U.S.,but only light, scattered snow over
the Upper Midwest/Great Lakes. Mostly light rain/mountain snow
should accompany a couple systems brushing the Pacific Northwest
and northern Rockies. Significant guidance differences with
separate streams of energy aloft lead to low confidence in the
coverage and amounts of precipitation over the South and East from
the weekend into early next week. Ambient cold air offers the
potential for some swaths of wintry weather on the northern
periphery of these uncertain precipitation areas, with best bet
Sunday over the Southeast/southern Mid-Atlantic.
Arctic high pressure settling from the central to eastern U.S.
behind the front will bring very cold temps later this week into
the weekend. Anomalies may be most profound for parts of the
southern Plains with values 15-25 degrees below normal possible.
Upper ridging trying to build across the northern/central Plains
Monday-Tuesday of next week could bring a period of much above
normal temperatures to this region.
Schichtel/Asherman
Hazards:
- Heavy snow from portions of the central Appalachians through
central/southern New England and southern Maine, Fri-Sat, Feb
4-Feb 5.
- Heavy snow for portions of the northern Cascades, Fri, Feb 4.
- Freezing rain across portions of the Mid-Atlantic to the
southern New England coast, Fri, Feb 4.
- Flooding possible across portions of southeastern Texas.
- Much below normal temperatures across portions of the southern
Rockies to much of the southern Plains, Fri-Sun, Feb 4-Feb 6.
- Much below normal temperatures across portions of the central
and southern Plains, into the lower and mid-Mississippi Valley,
Ohio Valley and portions of the southern Rockies, Fri, Feb 4.
Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php
WPC medium range 500mb heights, surface systems, weather grids,
quantitative precipitation, winter weather outlook probabilities
and heat indices are at:
https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif
https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html
https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml