Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
149 PM EST Mon Feb 07 2022
Valid 12Z Thu Feb 10 2022 - 12Z Mon Feb 14 2022
1900 UTC update...
The latest 00z/06z model guidance continues to show a similar
evolution and thinking compared to previous runs and so no major
changes were needed from the overnight WPC forecast package. The
06z GFS continued to be an outlier with very little to no support
from other pieces of guidance with a cut off closed low over the
Southwest U.S. this weekend and so it was excluded from the WPC
blend after day 4. However, the 12z GFS did come in without that
feature so that is something to note. After day 5, the timing of
systems within the mean East trough as well as amplitude and
timing of an incoming Pacific Northwest shortwave on day 7
continue to present forecast issues. Therefore, a blend away from
the deterministic solutions with more emphasis towards the
ensemble means seemed a safe starting point for the updated
forecast and also provided excellent continuity with the previous
WPC progs. See previous discussion below for additional
information and details regarding model guidance and sensible
weather impacts.
Santorelli
Previous discussion issued at 0700 UTC...
...Weather Pattern Overview...
It remains the case that a rather amplified upper level pattern
will be in place for this forecast period with a synoptic scale
ridge centered near the West Coast through Sunday, and a broad
trough with multiple embedded shortwaves/fronts over the eastern
half of the nation. There is some signal of a potential pattern
change by early next week as a more active storm track over the
northeast Pacific tries to break down the West Coast ridge.
...Guidance Evaluation/Predictability Assessment...
Models and ensemble means remain generally in reasonable agreement
with the larger scale upper-pattern this week, albeit with some
timing and focus differences noted with many of the individual
shortwaves. By Saturday, the 00Z GFS becomes quite amplified with
the trough dropping south across the Rockies and forms a closed
low that lacks ensemble support, but the 18Z was able to be
incorporated into the fronts/pressures forecast. By next Monday,
the ECMWF becomes very strong with a closed low off the Oregon
Coast, whereas the GFS/CMC favor a more modest shortwave trough.
For the large scale trough developing over the eastern U.S. this
weekend, it still appears that the axis will be positively tilted
and little in the way of phasing regarding northern/southern
stream energy, and this will limit the potential for surface
cyclogenesis off the East Coast as it stands right now.
The WPC fronts/pressures forecast was primarily derived from a
deterministic blend through Friday, and then gradually increasing
percentages of the means through next Monday. For QPF, more of
the ensemble biased corrected model, along with some of the
CMC/GFS/ECMWF, was used since the NBM appears too light with its
QPF across the north-central U.S. for the end of the week.
...Weather Highlights/Threats...
The majority of the continental U.S. will enjoy dry weather and
little in the way of disruptive weather through the weekend.
There has been a gradual increase with expected snowfall totals
across the Upper Midwest and Great Lakes region with the strong
clipper system for the end of the week, with some potential for
3-6 inch accumulations across portions of northern Minnesota,
northern Michigan, and downwind of Lakes Erie and Ontario.
Farther south, there will likely be an emerging area of showers
from the central Gulf Coast and the Florida Peninsula to the
Southeast U.S. coast over the weekend as moisture flows northward
ahead of an approaching cold front.
In terms of temperatures, the majority of the nation should be
near to slightly above average for highs to close out the week,
with the greatest warm departures on the order of 15-25 degrees
for portions of the Northern Plains on Thursday. With the trough
building in across the east-central U.S. in time for the weekend,
expect a return to reality with highs running up to 15 degrees
below average from the Great Lakes to the Ohio Valley and
Northeast. It should be mild once again across most of the Plains
for Sunday and into Monday.
Hamrick
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