633
FXUS06 KWBC 081902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Wed October 08 2025

6-10 DAY OUTLOOK FOR OCT 14 - 18 2025

Today`s dynamical models are in relatively good agreement in predicting an
amplified 500-hPa circulation pattern across much of the forecast domain. A
moderately deep, anomalous trough is forecast to extend southwestward from the
Arctic Ocean across northern and western Alaska, eastern Siberia, the Bering
Sea, and nearby northern Pacific Ocean. A strong anomalous ridge with
associated positive height anomalies is predicted over the eastern Pacific
(including the Gulf of Alaska), with the largest positive anomalies located in
the general vicinity of 50N/140W. As time progresses, this ridge is forecast to
break down as the flow becomes more zonal. Downstream, a moderately strong
mid-level trough is forecast near the West Coast of the Contiguous U.S.
(CONUS). Farther east, ridging and associated above normal heights are
predicted over the Central and most of the Eastern CONUS west of the
Appalachians, with the largest positive departures over most of the Mississippi
Valley and Great Plains. A mid-level trough is forecast just off the Atlantic
coast, which is stronger in today`s model runs than it was in yesterday`s runs.
Near normal heights continue to be forecast for Hawaii by today`s ensemble
means.

Below normal temperatures are favored across most of the western quarter of the
CONUS due to the proximity of a predicted trough. Downstream ridging and
positive height anomalies elevate the chances of above normal temperatures
across much of the remainder of the Lower 48 states. There are some differences
in the reforecast temperature tools near the East Coast, with the GEFS being
the warmest solution, followed by the ECENS and then CMCE, with the latter
featuring a mix of below, near, and above normal temperatures east of the
Appalachians. The consolidated temperature tool provides a reasonable
compromise between the GEFS and ECENS solutions, while the majority of the raw
and bias-corrected temperatures favor a somewhat cooler solution for the
Atlantic coast states. Maximum chances favoring above normal temperatures
exceed 80 percent over the Southern Plains. Above normal temperatures are
favored across most of Alaska due to predicted enhanced southwesterly onshore
flow between a trough over the Bering Sea and western Alaska and a ridge over
the Gulf of Alaska and Southeast Alaska. Above normal temperatures are likely
for Hawaii (particularly the western and central islands), consistent with
above normal sea-surface temperatures (SSTs) in the adjacent Pacific Ocean.

Wetter-than-normal conditions continue to be favored over much of the western
and north-central CONUS. This is due to the proximity of a significant
mid-level trough forecast near the West Coast, and the predicted influx of
tropical moisture from the eastern Pacific associated with the remnants of at
least one, and possibly two tropical systems (from what is currently Tropical
Storm Priscilla and the developing system behind it). This possibility is most
likely to occur just prior to, and during the early stages of, the 6-10 period.
The north-central CONUS is forecast to be influenced by low pressure moving
across central Canada, with its associated trailing cold front tapping into
moisture streaming out the Southwest U.S. Chances of above normal precipitation
peak over 60 percent across central sections of California. A low pressure
system predicted off the upper Mid-Atlantic coast early in the forecast period
is expected to slowly track northeastward, spreading wraparound precipitation
across the Northeast coastal plain, before departing the region. Therefore,
above normal precipitation is favored for New England, with near normal
precipitation over New York state, New Jersey, and eastern Pennsylvania. Behind
the offshore storm system, and to the east of the mean subtropical ridge axis
over northern Mexico and Texas, a large area of below normal precipitation is
favored. This includes approximately the southeastern quarter of the CONUS,
nosing northeastward over the Ohio Valley, central Appalachians, and portions
of the Mid-Atlantic. An active pattern is likely for most of Alaska due to
forecast onshore flow associated with the predicted ridge to the south of the
state. Probabilities of above normal precipitation exceed 60 percent for parts
of western Alaska.  Above normal precipitation is also favored for Hawaii,
consistent with a consolidation of calibrated precipitation amounts from the
GEFS and ECMWF ensembles.

The official 6-10 day 500-hPa height blend consists of 30% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 40% of Today`s 0z European Ensemble Mean
centered on Day 8, and 30% of Today`s 0z Canadian Ensemble Mean centered on Day
8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Above average, 4 out of 5, due to
fairly good agreement among today`s ensemble means in depicting an amplified
500-hPa pattern across much of the forecast domain.

8-14 DAY OUTLOOK FOR OCT 16 - 22 2025

During week-2, anomalous troughing persists over the vicinity of the Bering Sea
and far western Alaska. Downstream ridging continues to flatten out,
overspreading western Canada with Pacific air. A trough is forecast to persist
near the U.S.West Coast (though weaken relative to the earlier 6-10 day
period), with fast low-amplitude flow across the remainder of the CONUS. The
manual height blend depicts weak positive height anomalies and weak ridging
over the southern Rockies, Plains, and Mississippi Valley. Near to below normal
500-hPa heights are predicted for the Atlantic coast states, with the greater
negative departures over and just east of New England. The center of the
predicted mean subtropical ridge is forecast over northern Mexico and southern
Texas. Today`s ensemble means continue to forecast near-normal heights over the
Hawaiian Islands.

Above normal temperatures are favored for the Central CONUS and much of the
Southeast, in addition to northern New England. This is attributed to above
normal mid-level heights and/or anomalous ridging over most of this large area.
For northern New England, warmer-than-normal mean temperatures are favored near
and east of a mid-level trough axis. The maximum chances for above normal
temperatures exceed 70 percent over parts of Texas. For most of the western and
eastern thirds of the CONUS, near to below normal temperature chances are
elevated based on the predicted proximity of mid-level troughs and cold air
advection. This is well supported by raw and bias-corrected temperatures from
the various models, and to a lesser extent the ECENS and CMCE ensemble means.
Southwesterly anomalous flow into Alaska tilts the odds towards
warmer-than-normal temperatures for most of the state, with the exception of
near normal temperatures favored over southern portions of Southeast Alaska.
Above normal temperatures are likely for Hawaii (particularly the western and
central islands), consistent with above normal SSTs in the adjacent Pacific
Ocean.

The week-2 precipitation outlook is fairly similar to that of the preceding
6-10 day period. Odds for above normal precipitation are elevated for much of
the western and north-central CONUS, in addition to northern New England, based
on the same reasoning as for the earlier period, though northern New England is
expected to be near and just east of a 500-hPa trough axis. A slight tilt
favoring below normal precipitation is indicated from the southern Plains
eastward across the Gulf Coast states to the Southeast coast, and northeastward
over the Tennessee Valley, Upper Ohio Valley, most of the Appalachians, and
Mid-Atlantic region. This is based on raw precipitation amounts from the
various models, the consolidation, and the automated precipitation tools. This
anomalously dry area (though probabilities are modest) is bookended by the mean
subtropical ridge axis over northern Mexico and Texas, and the area behind the
oceanic storm system as it moves farther out to sea. In other words, this large
region is forecast to be in an environment dominated by subsidence. An active
pattern is favored to persist across most of Alaska ahead of a trough over the
Bering Sea.  Above normal precipitation is favored for Hawaii, consistent with
a consolidation of calibrated precipitation amounts from the GEFS and ECMWF
ensembles.

The official 8-14 day 500-hPa height blend consists of: 30% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 40% of Today`s 0z European Ensemble Mean
centered on Day 11, and 30% of Today`s 0z Canadian Ensemble Mean centered on
Day 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Near average, 3 out of 5, due to
fairly good model agreement on the 500-hPa circulation pattern, offset by
uncertainties regarding a deamplifying flow pattern and associated increase in
uncertainty in the surface temperature and precipitation fields.

FORECASTER: Anthony A

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 (unshaded, "N"). Historical average
values for the calendar period of the forecast (dashes, "f").  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 (unshaded, "n"). Historical median values
for the calendar period of the forecast (dashes, "inches").  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
October 16.


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:
19611019 - 20070918 - 19710922 - 20050923 - 19610924


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:
19610922 - 19831002 - 20070917 - 19831010 - 19710921


6-10 DAY OUTLOOK TABLE
Outlook for Oct 14 - 18 2025

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



8-14 DAY OUTLOOK TABLE
Outlook for Oct 16 - 22 2025

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

                           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.

$$