778
FXUS06 KWBC 012001
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EST Mon December 01 2025

6-10 DAY OUTLOOK FOR DEC 07 - 11 2025

Model ensembles from the ECENS, GEFS, and CMCE are in fair agreement with
respect to the synoptic picture over North America as depicted in 500-hPa
height anomalies during the 6-10 day forecast period, however model solutions
begin to diverge towards the end of the forecast period. Today`s 500-hPa manual
blend depicts moderate ridging over the North Pacific and extending into the
western Contiguous U.S. (CONUS), and a broad and amplified trough covering most
of North America east of the Rocky Mountains and extending well into the North
Atlantic. This trough extends upstream in the high latitudes to cover much of
Alaska, with amplified ridging upstream of that over eastern Siberia.

With an amplified trough centered over Quebec and a blocking ridge upstream,
much of the eastern CONUS is favored for below-normal temperatures,
particularly over the Great Lakes and New England, where probabilities exceed
60%. These chances decline quickly going south, with near- to above-normal
temperatures more likely for much of the Southeast U.S. and Gulf Coast. The
blocking ridge over the North Pacific also favors above-normal temperatures for
the western Great Plains and the western CONUS, with the highest probabilities
(>70%) over the interior Northwest and Great Basin. A similar dynamic, with
troughing over Alaska and amplified ridging over eastern Siberia, favors
below-normal temperatures for the entire state, especially along the
southwestern coast where probabilities exceed 80%. Positive height anomalies
over much of the North Pacific favor above-normal temperatures for the Hawaiian
Islands.

Extensive troughing over much of North America sets up two sources of moisture
to drive enhanced precipitation, one focused on the Canadian West Coast fed by
the North Pacific, and the second along the East Coast as Gulf moisture streams
into a baroclinic zone driven by the deep mid-level trough. This favors
above-normal precipitation for much of the northern CONUS, especially along
western portions of the U.S.-Canadian border (>60% chances) and along the East
Coast, with chances exceeding 50% for southern Florida. Ridging over the
southwestern CONUS diverts these moisture streams away from the southwestern
CONUS and beyond, tilting the odds towards below-normal precipitation for much
of the Southern and Central Plains, as well as the Desert Southwest and much of
California. Like the temperatures, a similar dynamic plays out in Alaska, with
below-normal precipitation favored over much of the northern and western
Mainland, and above-normal precipitation preferred over the Panhandle. Hawaii
tilts towards above-normal precipitation, consistent with most forecast tools.

The official 6-10 day 500-hPa height blend consists of 33% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 34% of Today`s 0z European Ensemble Mean
centered on Day 8, and 33% of Today`s 0z Canadian Ensemble Mean centered on Day
8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Above average, 3 out of 5. Fair
agreement among the temperature and precipitation dynamical and statistical
tools, offset by diverging model solutions with respect to evolution of
synoptic features.

8-14 DAY OUTLOOK FOR DEC 09 - 15 2025

Most model solutions generally indicate a persistence of synoptic features
across the forecast domain early in week-2, but by the second half of the
forecast period model ensemble solutions diverge significantly in depicting
synoptic flow over North America. Yesterday the GEFS indicated a trough-ridge
pattern out of phase with the ECENS and CMCE solutions, but today the CMCE is
the odd model out, being out of phase with GEFS and ECNES solutions. Regardless
of this lack of clarity, the week-2 500-hPa height manual blend shows a
persistence of synoptic features seen in the 6-10 day period, likely due to
coherent signals early and conflicting signals cancelling out, potentially
masking out what might be an upcoming shift in large-scale flow that is often
preceded by increased model spread such as this.

Below-normal temperatures continue to be favored for the northeastern CONUS,
with odds topping 50% for much of the Northeast U.S. The Southern and Central
Plains as well as the whole of the western CONUS continue to tilt towards
above-normal temperatures with chances generally increasing from east to west.
Below-normal temperatures are likely to persist over the state of Alaska, while
ridging over the North Pacific favors continuing above-normal temperatures for
Hawaii.

Continued ridging over the North Pacific is likely to keep much of the Southern
Tier west of the Mississippi River under below-normal precipitation, while its
upstream influence is favored to spread beyond the Central Plains, tilting
portions of the Middle Mississippi and Tennessee Valleys, and the Mid-Atlantic
towards near-normal precipitation. The northern CONUS remains favored for
above-normal precipitation, with higher chances (>50%) along the western
U.S.-Canadian border. Southeast Alaska remains close enough to the main Pacific
storm track to tilt towards above-normal precipitation, while most of Mainland
Alaska remains under below-normal precipitation. All of Hawaii tilts towards
above-normal precipitation, consistent with most forecast tools.

The official 8-14 day 500-hPa height blend consists of: 33% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 34% of Today`s 0z European Ensemble Mean
centered on Day 11, and 33% of Today`s 0z Canadian Ensemble Mean centered on
Day 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Below average, 2 out of 5.
Increasing spread being seen in ensemble solutions, especially towards the end
of the forecast period, offset by good agreement among temperature and
precipitation tools.

FORECASTER: Daniel Barandiaran

Notes:


The notation for the categorical forecast indicated on the maps is
the same as that in the tables: A-above   N-near normal   B-below

The temperature map shows regions with > 33% chance of being warmer
(orange, "A"), colder (blue, "B"), or close to (gray, "N") normal.
Labels on the shaded lines give the probability (> 33%) of the more
likely category (B or A). Probability of N is always < 40%.

The precipitation map shows regions with > 33% chance of being
wetter (green, "A"), drier (tan, "B"), or close to (gray, "N")
normal. Labels on the shaded lines give the probability (> 33%) of
the more likely category (B or A). Probability of N is always < 40%.

In the southwest and other climatologically dry regions - there will
be a greater than 33.3% chance of no precipitation and occasionally
even a normal (i.e. Median) value of zero - especially during the dry
seasons.  In such cases a forecast of near normal is effectively a
forecast of little or no precipitation.

The climate prediction center uses 1991-2020 base period means as
reference in the climate outlooks.

The next set of long-lead monthly and seasonal outlooks will be released on
December 18.


Analogs to the 5 day mean observed pattern centered 3 days ago (D-3)
for the region from 20N to 70N latitude and 175E to 60W longitude
include the 5 day periods centered on the following dates:
20081204 - 20071125 - 19881208 - 20021203 - 19761127


Analogs to the 7 day mean observed pattern centered 4 days ago (D-4)
for the region from 20N to 70N latitude and 175E to 60W longitude
include the 7 day periods centered on the following dates:
19781125 - 20071126 - 20081203 - 19761130 - 20021203


6-10 DAY OUTLOOK TABLE
Outlook for Dec 07 - 11 2025

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    A     OREGON      A    A     NRN CALIF   A    B
SRN CALIF   A    B     IDAHO       A    A     NEVADA      A    B
W MONTANA   A    A     E MONTANA   A    A     WYOMING     A    A
UTAH        A    B     ARIZONA     A    B     COLORADO    A    B
NEW MEXICO  A    B     N DAKOTA    B    A     S DAKOTA    A    A
NEBRASKA    A    N     KANSAS      A    B     OKLAHOMA    A    B
N TEXAS     A    B     S TEXAS     A    B     W TEXAS     A    B
MINNESOTA   B    A     IOWA        B    N     MISSOURI    B    B
ARKANSAS    N    B     LOUISIANA   N    B     WISCONSIN   B    A
ILLINOIS    B    N     MISSISSIPPI N    B     MICHIGAN    B    A
INDIANA     B    N     OHIO        B    N     KENTUCKY    B    N
TENNESSEE   B    N     ALABAMA     N    N     NEW YORK    B    A
VERMONT     B    A     NEW HAMP    B    A     MAINE       B    N
MASS        B    A     CONN        B    A     RHODE IS    B    A
PENN        B    A     NEW JERSEY  B    A     W VIRGINIA  B    N
MARYLAND    B    A     DELAWARE    B    A     VIRGINIA    B    N
N CAROLINA  B    N     S CAROLINA  B    A     GEORGIA     N    A
FL PNHDL    N    A     FL PENIN    A    A     AK N SLOPE  B    B
AK ALEUTIAN B    B     AK WESTERN  B    B     AK INT BSN  B    B
AK S INT    B    B     AK SO COAST B    N     AK PNHDL    B    A



8-14 DAY OUTLOOK TABLE
Outlook for Dec 09 - 15 2025

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    A     OREGON      A    A     NRN CALIF   A    B
SRN CALIF   A    B     IDAHO       A    A     NEVADA      A    B
W MONTANA   A    A     E MONTANA   A    A     WYOMING     A    A
UTAH        A    B     ARIZONA     A    B     COLORADO    A    N
NEW MEXICO  A    B     N DAKOTA    N    A     S DAKOTA    A    A
NEBRASKA    A    N     KANSAS      A    B     OKLAHOMA    A    B
N TEXAS     A    B     S TEXAS     A    B     W TEXAS     A    B
MINNESOTA   N    A     IOWA        N    N     MISSOURI    N    B
ARKANSAS    A    B     LOUISIANA   A    B     WISCONSIN   B    A
ILLINOIS    B    N     MISSISSIPPI A    N     MICHIGAN    B    A
INDIANA     B    N     OHIO        B    N     KENTUCKY    B    N
TENNESSEE   B    N     ALABAMA     N    N     NEW YORK    B    A
VERMONT     B    A     NEW HAMP    B    A     MAINE       B    A
MASS        B    A     CONN        B    A     RHODE IS    B    A
PENN        B    A     NEW JERSEY  B    A     W VIRGINIA  B    N
MARYLAND    B    N     DELAWARE    B    N     VIRGINIA    B    N
N CAROLINA  B    N     S CAROLINA  B    N     GEORGIA     N    N
FL PNHDL    N    A     FL PENIN    N    A     AK N SLOPE  B    B
AK ALEUTIAN B    N     AK WESTERN  B    B     AK INT BSN  B    B
AK S INT    B    B     AK SO COAST B    B     AK PNHDL    B    A

                           LEGEND
TEMPS WITH RESPECT TO NORMAL     PCPN WITH RESPECT TO MEDIAN
A - ABOVE   N  - NEAR NORMAL     A - ABOVE   N - NEAR MEDIAN
B - BELOW                        B - BELOW

THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.

FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS
PMDMRD.

$$