462
FXUS06 KWBC 291902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Tue July 29 2025

6-10 DAY OUTLOOK FOR AUG 04 - 08 2025

The ECMWF, GEFS and Canadian ensemble models broadly agree on the 500-hPa
height pattern over North America and surrounding regions during the 6-10 day
period, with only minor variations among the models in terms of amplitude and
phase of predicted wave features. The manual height blend is based on 0Z
ensemble means, weighing the ECMWF model greater due to recent model anomaly
correlation skill. The manual blend shows a modest mid-level trough across the
Bering Sea and northern Gulf of Alaska, with below normal heights favored over
the central and eastern Aleutians. Mid-level troughs in the full height field
are depicted over the northwestern and northeastern Contiguous U.S. (CONUS).  A
594-dm height contour is predicted over the southwestern and south-central
CONUS. The northeastern trough is associated with positive height anomalies
that extend northward across much of eastern and central Canada.

Above normal temperatures are favored for Mainland Alaska and northern areas of
Southeast Alaska, as indicated by the reforecast-calibrated temperature tools.
Near normal temperatures are slightly favored for southern areas of Southeast
Alaska, due to conflicting and weak indications. Above normal temperatures are
favored from much of the Four Corners region and Central CONUS eastward to near
the Appalachian Mountains, interior Northeast, Florida, and the coastal
Southeast. Maximum probabilities of 70-80% are indicated over the southern High
Plains. This is generally associated with positive mid-level height departures
and a broad area of predicted low-level southerly flow. Below normal
temperatures are favored across much of the western CONUS, under a weak trough
and consistent with dynamical models. Above normal temperatures are likely for
Hawaii, consistent with the temperature consolidation.

Below normal precipitation is favored for parts of western Mainland Alaska,
while above normal precipitation is favored for the southern coast and the
eastern Mainland, consistent with the precipitation consolidation of calibrated
model precipitation forecasts. For the CONUS, above normal precipitation is
favored from the Pacific Northwest eastward into the Northern Plains, along and
ahead of a weak trough. Above normal precipitation is slightly favored for much
of the eastern CONUS, consistent with the consolidated and automated
precipitation tools. Below normal precipitation is favored from approximately
the central and southern Intermountain region eastward to the central and
southern Plains, under a predicted ridge and well removed from the main storm
track. Below normal precipitation is also favored over parts of the Northeast,
under positive 500-hPa height anomalies. Above normal precipitation is favored
for Hawaii, consistent with the consolidation.

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
good agreement between ensemble models on the mid-level height pattern
forecast, offset by some differences among temperature and precipitation
forecast tools.

8-14 DAY OUTLOOK FOR AUG 06 - 12 2025

Ensemble mean forecasts for the 500-hPa circulation pattern over North America
remain in general agreement during the 8-14 day period, while the overall
pattern deamplifies. A weak trough is predicted to be centered over the
northern Gulf of Alaska, with ridging upstream over the western Aleutians and
western Bering Sea. Low amplitude westerly flow is forecast across the northern
tier of the Lower 48, with a 594-dm contour persisting across the Southwest.
Most of the CONUS is predicted to have positive height anomalies during the
forecast period, with the exceptions of the Gulf states and the Southeast, and
the Northern Plains where 500-hPa heights are forecast to be near normal.

Above normal temperature chances are elevated for most of the southern and
central Mainland of Alaska, except for the northwestern and northern coast, and
the Alaska Panhandle,  where near to below normal temperatures are favored,
consistent with the consolidation and automated temperature tools. Above normal
temperatures are favored for almost the entirety of the CONUS in week 2, under
a predominance of positive 500-hPa height anomalies. Near normal temperatures
are slightly favored for parts of the Northern Rockies, as a weak trough over
the region deamplifies. Above normal temperatures are favored for Hawaii,
supported by the consolidation tool.

Below normal precipitation remains favored for much of the southwestern quarter
of the CONUS, based on the consolidation and various raw precipitation tools.
Above normal precipitation is slightly favored from the Pacific Northwest
eastward across parts of the northern tier states, and over a large fraction of
the eastern CONUS. This is supported to various degrees by the raw model
precipitation probabilities, and the GEFS and ECENS reforecasts (in particular
the latter which predicts a more zonal flow pattern across the Northern Rockies
versus the GEFS which forecasts a more amplified solution). Above normal
precipitation is also favored over the central and eastern thirds of Alaska,
and all of the Hawaiian Islands.This is based primarily on the automated and
consolidated precipitation tools.

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
good overall agreement on the mid-level height forecast, offset by a
deamplifying pattern and weak signals in the precipitation tools for most areas.

FORECASTER: Anthony A

Notes:


Automated forecasts are issued on Saturday and Sunday. Occasionally manual
intervention is necessary to address quality control and consistency issues. In
these cases, forecasts are manually drawn but a full discussion is not issued.


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
August 21.


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:
19600711 - 20010810 - 19530724 - 19860719 - 19770718


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:
19600711 - 19530723 - 20010808 - 20030711 - 19930729


6-10 DAY OUTLOOK TABLE
Outlook for Aug 04 - 08 2025

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



8-14 DAY OUTLOOK TABLE
Outlook for Aug 06 - 12 2025

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

$$