179
FXUS06 KWBC 151902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Sat August 15 2026

6-10 DAY OUTLOOK FOR AUG 21 - 25 2026

Dynamical models are in good agreement regarding the 500-hPa height pattern
across North America during the 6-10 day forecast period. Mid-level ridging is
forecast to retrograde across the southern CONUS, with some increase in
amplitude toward day-10 as it moves into the west-central CONUS. This feature
favors a broad area of above-normal heights (at least +30 meters) in the manual
blend across the CONUS, with the only exception being over the Great Lakes into
the Northeast where near-normal heights are more likely tied to enhanced
troughing over eastern Canada. A pronounced height dipole pattern is forecast
across the north-Pacific in the vicinity of Alaska, with ridging and subsequent
above-normal heights over the western Aleutians and troughing centered over the
Arctic Ocean with periodic shortwaves digging into Alaska, favoring near-normal
heights across much of the Mainland into parts of Southeast Alaska. Near- to
slightly above-normal heights are forecast for Hawaii tied to ridging to the
north of the islands but offset by increased tropical activity predicted over
the eastern and central Pacific.

Increased probabilities for above-normal temperatures are favored for most of
the CONUS under ridging and above-normal 500-hPa heights, supported by most of
the dynamical temperature forecast tools. The highest chances for above-normal
temperatures (above 70 percent) are centered over the Four Corners, generally
collocated with the highest mean heights.  Near-normal temperatures are favored
for parts of the Great Lakes and Northeast, in proximity to a mid-level trough.
Above-normal temperature chances are elevated across Southeast Alaska
consistent with the GEFS and ECMWF reforecast tools, while below-normal
temperatures are forecast over the Aleutians and parts of western Mainland
Alaska with additional support from the uncalibrated guidance and analogs.
Above-normal temperatures remain favored in Hawaii with above-normal sea
surface temperatures and an increasing influence from El Nino.

Near- to 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.  Wetter-than-normal conditions are slightly favored along the Eastern
Seaboard due to a weak trough predicted over eastern Canada and associated
enhanced frontal or surface low activity. This is consistent with most of the
precipitation tools. Below-normal precipitation is slightly favored over
portions of the Southern and Central Plains as well as the Lower and Middle
Mississippi Valley, downstream from the Four Corners ridge. In Alaska, near to
above normal precipitation is slightly favored due to periodic enhanced onshore
flow associated with shortwave troughing. For Hawaii, above normal
precipitation is favored by the precipitation guidance tied to increased
influence from tropical cyclone activity across the eastern and central
Pacific, with the remnants of Tropical Storm Hernan potentially moving near the
islands during the period.

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, 4 out of 5, due to
good agreement among the dynamical model guidance, offset by weak signals in
the precipitation forecast across the CONUS.

8-14 DAY OUTLOOK FOR AUG 23 - 29 2026

The 0z ECMWF, GEFS, and Canadian ensembles remain locked into a stable
mid-level pattern across North America during week-2. Even late in week-2, a
593-594 dm ridge axis persists across the Four Corners and High Plains, with
the week-2 manual height blend depicting above-normal heights across the
interior western and central CONUS. Near-normal heights are forecast across the
Northeast due to continued influence from troughing over eastern Canada. The
same mid-level pattern as in the 6-10 day period remains forecast across Alaska
during week-2, with above-normal heights over the Aleutians and near-normal
heights across the rest of the state. Near-normal heights are forecast for
Hawaii.

Above-normal temperature chances continue to be elevated across most of the
CONUS during week-2, with the exception of near-normal temperatures over the
parts of the Northeast, 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, and extending northward into the Rockies where the ridge becomes more
amplified. Below-normal temperatures are favored over the Aleutians and parts
of western Mainland Alaska, while above-normal temperatures are forecast over
Southeast Alaska. Above-normal temperatures continue to be favored across
Hawaii, tied to above-normal SSTs and El Nino influence.

Near- to 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. There is a
slight tilt toward enhanced above-normal precipitation chances across the
Northeast, consistent with the proximity of a weak mid-level trough over
eastern Canada. Near- to below-normal precipitation is favored for much of the
Great Plains into the Midwest and Tennessee Valley due to more influence from
ridging and weak synoptic forcing for precipitation, with the analog guidance
depicting a stronger signal for below-normal precipitation. Above-normal
precipitation probabilities remain elevated across much of Mainland and
Southeast Alaska, with near--normal precipitation across the Aleutians and
Alaska Peninsula. Above-normal precipitation is forecast for Hawaii tied to
increased tropical moisture.

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: Above average, 4 out of 5, due to
good model agreement regarding a persistent pattern, offset by continued weak
signals for precipitation across the CONUS.

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
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:
20050816 - 20170807 - 20130801 - 20240805 - 20090806


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:
20050815 - 20170807 - 20130729 - 20160821 - 20240805


6-10 DAY OUTLOOK TABLE
Outlook for Aug 21 - 25 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    N     WYOMING     A    A
UTAH        A    A     ARIZONA     A    A     COLORADO    A    A
NEW MEXICO  A    N     N DAKOTA    A    N     S DAKOTA    A    N
NEBRASKA    A    N     KANSAS      A    N     OKLAHOMA    A    B
N TEXAS     A    B     S TEXAS     A    B     W TEXAS     A    N
MINNESOTA   A    N     IOWA        A    N     MISSOURI    A    N
ARKANSAS    A    N     LOUISIANA   A    B     WISCONSIN   A    N
ILLINOIS    A    N     MISSISSIPPI A    N     MICHIGAN    N    N
INDIANA     N    N     OHIO        N    N     KENTUCKY    A    N
TENNESSEE   A    N     ALABAMA     A    N     NEW YORK    N    N
VERMONT     N    N     NEW HAMP    N    N     MAINE       N    A
MASS        N    A     CONN        N    A     RHODE IS    N    A
PENN        N    N     NEW JERSEY  N    A     W VIRGINIA  N    N
MARYLAND    N    N     DELAWARE    N    A     VIRGINIA    A    N
N CAROLINA  A    A     S CAROLINA  A    N     GEORGIA     A    N
FL PNHDL    A    N     FL PENIN    A    N     AK N SLOPE  N    A
AK ALEUTIAN B    N     AK WESTERN  B    A     AK INT BSN  N    A
AK S INT    N    A     AK SO COAST N    A     AK PNHDL    A    A



8-14 DAY OUTLOOK TABLE
Outlook for Aug 23 - 29 2026

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

$$