ATTENTION: For more information on the addition of the experimental Rapid Onset Drought hazard type to the Climate Prediction Center's 8-14 Day Hazards Outlook (Contiguous U.S. and Alaska), please click HERE.
Composite Map
Day 8-14
Experimental Probabilistic Outlooks
Valid Saturday February 04, 2023 to Friday February 10, 2023
US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM
EST January 27 2023
Synopsis: Surface high pressure is expected
to briefly result in an increased risk of much-below normal temperatures across
the Northeast on February 4 and 5. A low pressure system, with enhanced onshore
flow, is forecast to track eastward from the Pacific Northwest to the northern
Rockies from February 4 to 6. Beginning on February 8, mid-level high (low)
pressure is expected to build over Alaska (western U.S.)
Hazards
Moderate risk of much below-normal temperatures for parts of the
Northeast, Sat, Feb 4.
Slight risk of much below-normal temperatures for the Northeast, Sat-Sun,
Feb 4-5.
Slight risk of much below-normal temperatures for the northern Great
Plains, Wed-Fri, Feb 8-10.
Slight risk of heavy precipitation for portions of California, Oregon, and
Washington, Sat-Mon, Feb 4-6.
Slight risk of heavy snow for northern Coastal Range, Cascade Range, Sierra
Nevada Mountains, and Northern Rockies, Sat-Mon, Feb 4-6.
Slight risk of high winds for portions of California, Oregon, and
Washington, Sat-Mon, Feb 4-6.
Slight risk of heavy precipitation for eastern Oklahoma and Texas, lower
Mississippi Valley, and Ohio to Tennessee Valleys, Wed-Fri, Feb 8-10.
For Saturday February 04 -
Friday February 10: A short-lived and transient outbreak of Arctic air is
forecast for the Northeast on Feb 4 and 5, as a deep anomalous 500-hPa trough
rotates through southeastern Canada. On Feb 4, a moderate risk of much
below-normal temperatures is posted for northern New York and New England where
the reforecast tools depict minimum temperatures having a 40 percent chance of
falling below the 15th percentile. Uncalibrated model solutions feature minimum
temperatures below -10 degrees F in the outlined area for a moderate risk. A
slight risk of much below-normal temperatures continues through Feb 5, but
beyond this time, a rapid warming trend is likely with above-normal
temperatures forecast across the East by Feb 8.
Moderating temperatures are expected across the central U.S. by Feb 4 as
the core of Arctic air rapidly shifts eastward. Later in week-2, the ensemble
means are converging on a more typical La Nina pattern with an amplifying ridge
over the Aleutians and Bering Strait with a downstream trough across western
North America. Model solutions are in better agreement with a full-latitude
ridge becoming established over Alaska and extending poleward, which would
eventually bring a renewed outbreak of Arctic air to at least the north-central
U.S. by mid-February. Given this evolving pattern along with support from
reforecast tools and uncalibrated temperature output, a slight risk of much
below-normal temperatures is posted for the northern Great Plains from Feb 8 to
10.
The GFS and ECMWF ensemble means remain consistent that a shortwave trough
progresses eastward from the northeastern Pacific to the Pacific Northwest and
northern Rockies early in week-2. This shortwave trough, reforecast tools, and
uncalibrated model output support a slight risk of heavy precipitation and snow
across the Pacific Northwest, northern California, and the northern Rockies
from Feb 4-6. The enhanced onshore flow, associated with the shortwave trough,
also results in a slight risk of high winds for the Pacific Northwest and
northern California. In response to the amplifying ridge upstream over the
north-central Pacific and Alaska, a longwave trough is expected to develop
across the West later in week-2. Downstream of this longwave trough axis along
with return Gulf moisture, there is an increasing risk of heavy precipitation
for the south-central U.S. and a corresponding hazard is posted from Feb 8 to
10. Although a heavy snow hazard is not posted for the north-central U.S. due
to weak signals at this time, the evolving longwave pattern would begin to
increase a winter storm risk for this region by mid-February.
The week-2 temperature outlook for Alaska will be dependent on the
longitudinal placement of the amplifying ridge axis. Southeastern Alaska is the
most likely area to experience below-normal temperatures with model solutions
depicting an Arctic surface high centered to the east. Since the signal for
much below-normal temperatures is relatively weak, a temperature hazard is not
posted at this time.
Forecaster: Brad Pugh
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Please consult local NWS Forecast Offices for short range forecasts and region-specific information.