862
FXUS06 KWBC 291914
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Tue September 29 2026

6-10 DAY OUTLOOK FOR OCT 05 - 09 2026

The 0Z ECMWF, GEFS, and Canadian ensemble model forecasts predict a variable
500-hPa height pattern over the North America region during the 6-10 day
period. All ensemble means predict an amplified trough over the Bering Sea and
Alaska Peninsula at the start of the forecast period. The predicted trough
extends southeastward into the North Pacific to the north of Hawaii during the
middle of the period, before retrogressing toward the Alaska Peninsula later in
the period. There are small variations in the location of negative 500-hPa
height anomalies associated with this trough among the ECMWF, GEFS, and
Canadian ensemble means. A ridge and positive 500-hPa height anomalies are
predicted over the western and central contiguous United States (CONUS)
throughout the 6-10 day period. However, this ridge amplifies, as the trough to
the west extends southward, and then deamplifies later. A trough and associated
negative 500-hPa height anomalies over the northeastern CONUS at the start of
the 6-10 day period quickly progress eastward and are replaced by positive
500-hPa height anomalies in the ECMWF ensemble mean, before a trough and
negative 500-hPa height anomalies extend southward into the northeastern CONUS
from eastern Canada later in the 6-10 day period. The manual height blend is
based on the 0Z ECMWF, GEFS, and Canadian model 500-hPa height forecasts,
weighting the ECMWF ensemble mean greater due to recent model skill. A weak
trough and negative 500-hPa height anomalies are predicted over parts of the
Northeast in the 6-10 day manual blend.

Above normal temperatures are favored for the western Aleutian Islands, under
ridging during the period. Below normal temperatures are favored for
northwestern Mainland Alaska, under a trough and consistent with most model
temperature tools. Above normal temperatures are favored for southeastern
Mainland Alaska and likely for Southeast Alaska, under southerly flow ahead of
the predicted trough. There are high probabilities favoring above normal
temperatures for the western CONUS, under the predicted ridge. Probabilities
exceed 80 percent over a large area, under the amplifying ridge. Above normal
temperatures are also favored for the eastern Gulf Coast, under positive
500-hPa height anomalies early in the period. Below normal temperatures are
slightly favored for the Big Bend area and parts of central Texas, consistent
with most dynamical model temperature tools and the consolidation of calibrated
ECMWF and GEFS forecasts. Below normal temperatures are favored for much of the
northeastern CONUS, under variable troughing over the region in the 6-10 day
period. Below normal temperatures are slightly favored for the far northwestern
Hawaiian Islands, while above normal temperatures are favored for the
southeastern Hawaiian Islands, consistent with an automated blend of
temperature tools.

Above normal precipitation is favored for the Aleutian Islands, consistent with
the consolidation of calibrated ECMWF and GEFS precipitation forecasts. Above
normal precipitation is favored for southern and interior Mainland Alaska and
Southeast Alaska, under southerly flow ahead of the predicted trough. High
probabilities of below normal precipitation are forecast for the northwestern
CONUS eastward across the Northern and Central Plains into the Midwest, under
the predicted ridge. Above normal precipitation is favored for parts of the
Southwest near the border with Mexico, consistent with the precipitation
anomaly forecast from the consolidation. Above normal precipitation is likely
for central and southern Texas, the southeastern CONUS, and parts of Maine,
consistent with the consolidation anomaly forecast. Probabilities exceed 50
percent for above normal precipitation for much of the Gulf Coast and
Southeast, where predicted precipitation anomalies are greatest in the
consolidation. Near normal precipitation is favored for Hawaii, where
precipitation tools are inconsistent or indicate weak signals.

The official 6-10 day 500-hPa height blend consists of 25% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 50% of Today`s 0z European Ensemble Mean
centered on Day 8, and 25% 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
good agreement between model forecasts of the large-scale mid-level height
pattern, offset by differences in temperature and precipitation tools in some
areas.

8-14 DAY OUTLOOK FOR OCT 07 - 13 2026

The 0Z ECMWF, GEFS, and Canadian ensemble model forecasts remain relatively
consistent through most of week 2, despite a variable pattern. The manual
height blend for week 2 is based on the 0Z ECMWF, GEFS, and Canadian model
500-hPa height forecasts, weighting the ECMWF ensemble mean greater due to
recent model skill. The predicted 500-hPa height pattern in the manual blend
for the 8-14 day period is similar to the predicted pattern for the 6-10 day
period with some evolution of the pattern. Compared to the Canadian ensemble
mean, the ECMWF and GEFS ensemble means predict a greater amplitude trough and
negative 500-hPa height anomalies extending from the Bering Sea southward into
the North Pacific, to the north of Hawaii. All models predict a ridge and
positive 500-hPa height anomalies over the western and central CONUS in week 2,
with the greatest positive 500-hPa height anomaly predicted over the Northern
Rockies by the ECMWF model. The manual blend predicts negative 500-hPa height
anomalies over parts of the northeastern CONUS and weak anomalies over the Gulf
and Atlantic Coasts in week 2.

Above normal temperatures are favored for the western Aleutian Islands,
consistent with most dynamical model forecast tools. Below normal temperatures
are slightly favored for a small area of northwestern Mainland Alaska,
consistent with ECMWF model forecasts and the consolidation. Above normal
temperatures are favored for most of southern and eastern Mainland Alaska and
Southeast Alaska, under southerly flow ahead of the predicted trough. The
likelihood of above normal temperatures remains high for the western and
northern central CONUS in week 2, under a persistent ridge. Near normal
temperatures are favored for southeastern Texas, consistent with the calibrated
ECMWF temperature forecast. Below normal temperatures are slightly favored for
parts of the northeastern CONUS, under a predicted trough through much of the
period. Above normal temperatures are favored for the eastern Gulf Coast and
Florida, consistent with the consolidation anomaly forecast. Above normal
temperatures are favored across most of the Hawaiian Islands except for Kauai,
consistent with ECMWF model temperature forecasts and supported by positive sea
surface temperature anomalies in the vicinity.

Above normal precipitation is slightly favored across the Aleutians in week 2,
consistent with the precipitation consolidation. Under southerly flow ahead of
the predicted trough, above normal precipitation is favored across Mainland
Alaska and Southeast Alaska. As an amplified ridge persists over the western
and northern central CONUS, below normal precipitation is favored from the
northwestern CONUS extending eastward across most of the Great Plains, from the
Red River Valley north, and most of the Midwest. Above normal precipitation is
favored across a narrow band of the southern tier of the CONUS in week 2,
including parts of the Southwest border with Mexico, the Rio Grande Valley, the
Gulf Coast, and the Southeast, consistent with the precipitation consolidation
anomaly forecast. Probabilities exceed 50 percent for parts of the Southeast,
where precipitation signals are greatest. Near normal precipitation is favored
for Hawaii, consistent with a consensus of calibrated precipitation forecasts.

The official 8-14 day 500-hPa height blend consists of: 25% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 50% of Today`s 0z European Ensemble Mean
centered on Day 11, and 25% of Today`s 0z Canadian Ensemble Mean centered on
Day 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: About average, 3 out of 5, due to
general agreement between model forecasts of the large-scale mid-level height
pattern, temperatures, and precipitation, offset by increasing uncertainty
related to an evolving forecast pattern.

FORECASTER: D Collins

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
October 15.


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:
20230928 - 20211008 - 20051010 - 20240915 - 20240927


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:
20230928 - 20051012 - 20240928 - 20211004 - 20230923


6-10 DAY OUTLOOK TABLE
Outlook for Oct 05 - 09 2026

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



8-14 DAY OUTLOOK TABLE
Outlook for Oct 07 - 13 2026

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

$$