529
FXUS06 KWBC 121902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Wed August 12 2026

6-10 DAY OUTLOOK FOR AUG 18 - 22 2026

The 0Z ECMWF, GEFS, and Canadian ensemble mean forecasts are in fairly good
agreement on the average large-scale circulation pattern over North America for
the 6-10 day period. The manual height blend is based on 0Z ECMWF, GEFS, and
Canadian model 500-hPa height forecasts, weighting the ECMWF ensemble mean
greater due to recent model skill. The manual blend indicates negative 500-hPa
height anomalies and/or mid-level troughing centered over the southeastern
Bering Sea, near the West Coast of the Contiguous U.S. (CONUS), and portions of
the Northeast. Positive 500-hPa height anomalies and/or mid-level ridging are
dominant across the southcentral and southeastern states, and northern,
central, and eastern Alaska. A mid-level ridge is forecast north of the
Hawaiian Islands, with near to slightly above normal heights over the Islands
themselves.

Near to above normal temperatures are favored for most of the CONUS (except for
parts of northeast California and northwestern Nevada, where below normal
temperatures are slightly favored) under ridging and above normal 500-hPa
heights, supported by most of the dynamical temperature forecast tools. Maximum
chances favoring above normal temperatures range from 70-80 percent over the
south-central and southeastern CONUS, generally collocated with the highest
mean heights. Relatively small areas of below normal temperatures are slightly
favored over northern Maine in proximity to a mid-level trough. Above normal
temperature chances are elevated across most of Alaska during the 6-10 day
outlook period, based on mid-level ridging across the north and southerly flow
on the eastern side of a nearby Bering Sea trough, while below normal
temperatures are forecast over the Aleutians under below normal 500-hPa
heights. Above normal temperatures remain favored in Hawaii with above normal
sea surface temperatures and an increasing El Nino signature.

Above normal precipitation is favored across the West, associated with a trough
predicted along the West Coast and the influx of monsoon moisture from Mexico.
For approximately the northern third of the CONUS east of the Continental
Divide, wetter-than-normal conditions are slightly favored, associated with the
westerlies on the northern flank of the subtropical ridge to the south. This is
consistent with most of the available precipitation tools, and may be related
to passing shortwaves and MCS activity. Below normal precipitation is slightly
favored from the Southern Plains eastward to the South Atlantic coast beneath
subtropical ridging. In western Alaska, above normal precipitation is slightly
favored due to onshore flow in advance of a mid-level trough predicted over the
southeastern Bering Sea, and also over parts of Southeast Alaska. For Hawaii,
above normal precipitation is favored by the precipitation guidance, in
addition to the increasing possibility of a developing tropical cyclone
southeast of the islands.

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 Normal, 4 out of 5, good
agreement among the dynamical model guidance offset slightly by lower
confidence in the statistical tools.


8-14 DAY OUTLOOK FOR AUG 20 - 26 2026

The 0Z ECENS, GEFS, and CMCE solutions for the 8-14 day period predict a fairly
consistent 500-hPa circulation pattern relative to the 6-10 day period across
North America and the surrounding regions. The anomalous trough over the Bering
Sea and the Aleutians is predicted to weaken substantially during week-2 and
shift eastward. The major large-scale circulation feature continues to be the
broad, zonally-elongated ridge over much of the southern two-thirds of the
CONUS, which displaces the westerlies to near the Canadian border. Weak
mid-level troughs are still forecast near the West Coast and over portions of
the Northeast. Near normal 500-hPa heights are forecast over the Hawaii
Islands.

Above normal temperatures continue to be favored across most of the CONUS
during week-2, with the exception of near to below normal temperatures over the
Northeast and northern Great Lakes region, consistent with most of the
dynamical temperature forecast tools. The greatest chances for above normal
temperatures (60-70 percent) are still expected over parts of the south-central
and southeastern CONUS, approximately collocated with the highest mean heights
associated with the subtropical ridge. Below normal temperatures are favored
over the Aleutians and parts of the southwestern Mainland Alaska, while near to
above normal temperatures are forecast over the remainder of Mainland Alaska
and Southeast Alaska.  Above normal temperatures continue to be mostly favored
across Hawaii, for the same reasons mentioned in the earlier 6-10 day
temperature section.

Above normal precipitation is favored over the western and central CONUS. This
is supported by most of the precipitation forecast tools, and is related to the
West Coast trough and the influx of monsoon moisture. In the northeastern
CONUS, there is a slight tilt in the odds favoring above normal precipitation,
consistent with the proximity of a weak mid-level trough. Odds slightly favor
below normal precipitation across theGulf coast region, Florida, and portions
of Minnesota and Wisconsin largely due to the proximity of the subtropical
ridge. For most of Alaska and Hawaii, the same reasoning for the 6-10 day
precipitation outlook applies to week-2, warranting enhanced chances for above
normal precipitation.

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: Above average, 4 on a scale of
1-5, based on reasonable agreement among the various height, temperature, and
precipitation tools and a relatively stable flow pattern at the 500-hPa level.


FORECASTER: Luke H

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
August 20.


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:
20160819 - 20170805 - 20240804 - 20020801 - 20010809


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:
20160819 - 20170804 - 20240803 - 20160824 - 20130728


6-10 DAY OUTLOOK TABLE
Outlook for Aug 18 - 22 2026

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



8-14 DAY OUTLOOK TABLE
Outlook for Aug 20 - 26 2026

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    A     OREGON      A    A     NRN CALIF   A    A
SRN CALIF   A    A     IDAHO       A    A     NEVADA      A    A
W MONTANA   A    A     E MONTANA   A    A     WYOMING     A    A
UTAH        A    A     ARIZONA     A    A     COLORADO    A    A
NEW MEXICO  A    A     N DAKOTA    A    N     S DAKOTA    A    A
NEBRASKA    A    A     KANSAS      A    N     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    N
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    N    N
INDIANA     A    N     OHIO        A    N     KENTUCKY    A    N
TENNESSEE   A    N     ALABAMA     A    N     NEW YORK    N    N
VERMONT     B    N     NEW HAMP    B    N     MAINE       B    N
MASS        N    N     CONN        N    N     RHODE IS    N    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  A    A
AK ALEUTIAN B    N     AK WESTERN  A    N     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.

$$