Valid Thursday, February 28, 2019 to Monday, March 11, 2019
Summary of Forecasts and Hazards
US Hazards Outlook
NWS Climate Prediction Center College Park MD
EDT October 23 2020Synopsis
: *** Week-2 U.S. Hazards will be
updated by mid-afternoon ET today ***
The Week-2 U.S. Hazards Outlook features mid-level low pressure over
Alaska and near the Eastern Seaboard of the contiguous U.S., with moderately
strong mid-level high pressure over the western and central CONUS. A weak,
low-amplitude ridge is predicted across the Bering Sea. Hazards
- *** Week-2 U.S. Hazards will be updated by mid-afternoon ET today ***
- Moderate chance of much below normal temperatures over the Great Lakes,
Northeast, and the northern Mid-Atlantic, Fri-Sat, Oct 30-31.
- Slight chance of much below normal temperatures from the Middle and Upper
Mississippi Valley eastward to the Northeast and the Mid-Atlantic Coast,
Fri-Tue, Oct 30-Nov 3.
October 26 - Friday October 30: WPC Days 3-7 U.S.
Hazards For Saturday October 31 - Friday
*** Week-2 U.S. Hazards will be updated by mid-afternoon ET
Today’s GFS and ECMWF ensembles predict more progressive solutions compared
to yesterday, backing off on the idea of a closed low developing across the
Southwest CONUS. The ECMWF ensemble is significantly more progressive today
than the GEFS. A moderately strong 500-hPa ridge is predicted to extend across
the western and central CONUS during Week-2, and a mid-level trough is forecast
to propagate rapidly eastward, with the mean location of its axis near the
Atlantic Coast. Most of Alaska is forecast to be under a trough, with heights
within 30 meters of normal for the Week-2 period.
The more progressive model solutions today favor the eastward advection of
anomalously cold air into the Great Lakes and Northeast during Week-2, and a
rapid retreat of anomalously cold air from the Southwest and Great Plains.
Accordingly, a slight chance (20%) of much below normal temperatures (15th
percentile or lower) is indicated from the Middle and Upper Mississippi Valley
eastward to the Northeast and Mid-Atlantic Coasts, from Oct 30-Nov 3. A
moderate chance (40%) of much below normal temperatures is specified for the
Great Lakes region, the Northeast, and northern Mid-Atlantic, from Oct 30-31.
For the Northeast CONUS, both the ECMWF and GFS reforecast tools indicate
temperatures could reach the 5th percentile of the historical minimum
temperature distribution. There is also at least a 60% chance of minimum
temperatures falling below 28 deg F for most of the Northeast, which qualifies
as a hard freeze. Possible exceptions could include Long Island, NY, and the
immediate southern New England coast.
Early in the Week-2 period, a lingering frontal zone is forecast to bring
precipitation to parts of the Mid-Atlantic and Northeast, but the amounts are
expected to fall short of hazardous criteria. Similarly, onshore flow ahead of
a mid-level trough over Alaska is expected to bring precipitation to the
Southeast Panhandle region (2 inches over a 3-day period), but this amount is
not considered hazardous for this region during this time of year.
The first significant Santa Ana wind event of the season is expected in
southern California early next week, however this event is likely to time off
before the beginning of the Week-2 Hazards period. The high wind event was
therefore removed from today’s Outlook map.
Forecaster: Anthony Artusa
Click here to see a display of the GFS Ensemble Forecasts
Please consult local NWS Forecast Offices for short range forecasts and region-specific information.