Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
255 AM EDT Wed Mar 30 2022
Valid 12Z Sat Apr 02 2022 - 12Z Wed Apr 06 2022
...Guidance Evaluation/Predictability Assessment...
The WPC medium range product suite was mainly derived from a blend
of reasonably well clustered mid-larger scale guidance from the 18
UTC GFS/GEFS mean and the 12 UTC ECMWF/UKMET/Canadian/ECMWF
ensemble mean along with the 01 UTC National Blend of Models days
3-7 (Sat-next Wed). However, embedded smaller scale system
differences and ample run to run continuity variances remain
problematic. Accordingly, blend weighting was transitioned from
primarily the models days 3-5 to the ensemble means days 6/7 to
mitigate less predictable forecast components amid steadily
growing forecast spread. Overall, WPC product continuity is best
maintained with this plan and the forecast seems in line with a
similar composite of newer 00 UTC guidance.
...Overview and Weather Highlights/Threats...
A closed upper trough and deepened surface low will work into the
Canadian maritimes by Saturday. Expect lingering high winds across
New England in the wake of the low. The southern portion of a
trailing western Atlantic cold front will slow over Florida, the
Gulf of Mexico and into Mexico. Scattered to widespread showers
are expected near the front, particularly across Florida and
possibly the Gulf coast Saturday.
Across the West, a leading series of upper troughs and low
pressure systems with modest precipitation potential are expected
track through with varying degrees of uncertainty through the
weekend. Infusion of highly energetic Pacific jet flow will then
up the ante and work increasingly inland from the Northwest to the
Rockies/Plains early-mid next week. This should act to transport
deeper moisture to fuel an emerging precipitation focus for some
heavier rains and mountain enhancing snows, mainly across the
Northwest.
Downstream progression and systems out from the West and
increasing northern stream phasing potential over time may combine
to support uncertain cyclogenesis/frontogensis over the central
and eastern states next week. There is a growing guidance signal
for development of a building area of moderate to heavy rainfall
across the east-central U.S. and especially a more
unstable/convective South early-mid next week as deeper Gulf
moisture returns and interacts with the complex series of wavy
fronts and a stalled lead front.
Schichtel
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, experimental excessive rainfall
outlook, 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/#page=ero
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml