Prognostic Meteorological Discussion
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FXUS06 KWBC 231902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Sun August 23 2026

6-10 DAY OUTLOOK FOR AUG 29 - SEP 02, 2026

Today`s numerical models predict a high amplitude mid-level pattern across the
higher latitudes of North America and vicinity and a moderately amplified
pattern farther to the south across the CONUS. Strong anomalous 500-hpa ridges
are forecast over the Aleutians and over north-central Canada while anomalous
troughs are predicted off the coast of southwestern Canada and well north of
the Alaska Mainland. Farther to the south, anomalous ridging is forecast over
the southwestern CONUS while a trough is forecast over the Northeast. The ridge
in the Southwest is forecast to weaken throughout the period, peaking in
strength around day 6. Meanwhile the trough off the coast of southwestern
Canada is forecast to reload and strengthen toward the middle of the period.
Downstream, the trough over the Northeast is expected to persist through the
period. Modest mid-level height anomalies are forecast across most Mainland
Alaska, sandwiched between ridges to its east and west and troughs to its north
and south. However, strong positive height anomalies are forecast across the
Aleutians, associated with the anomalous ridge there. Generally near to
slightly above normal heights are forecast across Hawaii during the period.

Above normal temperatures are favored across much of the CONUS, underneath
predicted near to above normal mid-level heights. Confidence is very high
(greater than 80 percent chance) for above normal temperatures across the
Southern High Plains and parts of the adjacent Southwest, near the center of
the predicted anomalous mid-level ridge. In contrast, a slight tilt toward
below normal temperatures is indicated for the Pacific Northwest and adjacent
northern California, associated with a nearby trough and an associated frontal
boundary. Near normal temperatures are favored across parts of the Great Lakes,
Northeast, and the northern Ohio Valley, associated with a predicted trough. A
small area of slightly enhanced chances of below normal temperatures is
indicated for parts of northern Michigan, near or slightly behind the predicted
trough axis. Much of western and northern Alaska tilts cold, underneath
anomalous northerly mid-level flow. However, above normal temperatures are more
likely across parts of the Aleutians, due to anomalous ridging. Near normal
temperatures are favored for Southeast Alaska and parts of the eastern
Mainland, underneath slightly anomalous southeasterly mid-level flow. Hawaii is
likely to be warmer than normal, as SSTs near and to the south of the state are
currently above normal.

Expansive ridging favors below normal precipitation from the southern Plains to
the southern Rockies and adjacent areas of the Southwest. Above normal
precipitation is favored for the Pacific Northwest and adjacent areas of the
northern Rockies and northern California, ahead of a trough forecast offshore.
Above normal precipitation is favored along the Eastern Seaboard and adjacent
areas associated with a predicted trough over the Northeast. A frontal boundary
and areas of surface low pressure are predicted early in the period over the
East Coast, increasing precipitation chances. An area of modestly enhanced
above normal precipitation chances is indicated over the Corn Belt and
surrounding areas, associated with a frontal boundary. Above normal
precipitation is favored for much of Alaska underneath predicted cyclonic flow.
However, near normal precipitation is favored across parts of the southwestern
Mainland, due to the potential for low level offshore flow behind predicted
surface low pressure over the Gulf of Alaska. Above normal precipitation is
modestly favored for Hawaii, as typical trade wind weather returns in the wake
of Tropical Storm Moke.

The official 6-10 day 500-hPa height blend consists of 30% of Today`s 6z 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: Below Average, 2 out of 5, due to
conflicting precipitation guidance.

8-14 DAY OUTLOOK FOR AUG 31 - SEP 06, 2026

During the week-2 period, strong ridging over the Aleutians is expected to
weaken considerably, potentially allowing a trough to the north of the Mainland
to slide southward across northwestern parts of the state. Downstream ridging
over north-central Canada is forecast to continue well into week-2, becoming
the most dominant high latitude feature during the period. Farther to the
south, the trough over the coast of the Pacific Northwest is forecast to
persist at least through the middle of the period. Ridging across the southern
High Plains is expected to continue but weaken considerably. The trough over
the Great Lakes and Northeast is forecast to modestly strengthen near the
middle of week-2. Near to slightly above normal mid-level heights are forecast
to persist across Hawaii.

Above normal temperatures are likely to persist across a large portion of the
central and southern Lower 48 states as 500-hpa heights are expected to remain
near or above normal across most areas. Confidence remains high (greater than
70 percent chance) for above normal temperatures across the southern High
Plains and adjacent areas of the Southwest due to persistent ridging. Near to
below normal temperatures are favored for northern California, Pacific
Northwest, as well as the northeastern quadrant of the CONUS, due to nearby
troughs. Much of western and central Mainland Alaska tilts cold, due to the
potential for increased troughing as a ridge over the Aleutians weakens. Above
normal temperatures are slightly favored across parts of Southeast Alaska and
adjacent areas of the southeastern Mainland, ahead of the predicted trough.
Above normal temperatures are also favored for parts of the Aleutians
underneath the weakening ridge. Above normal temperatures remain likely across
Hawaii as SSTs near and to the south of the state are largely above normal.

Confidence is lower than normal regarding the precipitation forecast across
much of the country due to weak or conflicting guidance. Teleconnections from
nearby mid-level features were utilized to inform the forecast, particularly
from the ridge over north-central Canada and the troughs over the Northeast and
near the Pacific Northwest. Collectively this guidance supports below normal
precipitation across much of the southern Plains and Gulf Coast, and adjacent
areas of the Southeast. The northeastern and northwestern CONUS tilt wet,
associated with nearby troughs. Much of the Great Lakes region and surrounding
areas tilt dry as surface high pressure builds in behind the Northeast trough.
A weak tilt toward above normal precipitation is forecast for parts of the
Southwest, supported by dynamical model guidance. Above normal precipitation is
favored across most of Alaska underneath mean cyclonic mid-level flow. Above
normal precipitation is indicated across Hawaii, reflecting uncertainty in the
tropics.

The official 8-14 day 500-hPa height blend consists of: 30% of Today`s 6z 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: Below Average, 2 out of 5, due to
weak or conflicting guidance among precipitation tools.

FORECASTER: Scott 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
September 17.


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:
20220811 - 20240901 - 20240803 - 20170804 - 20240906


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:
20240830 - 20100803 - 20220810 - 20250905 - 20160823


6-10 DAY OUTLOOK TABLE
Outlook for Aug 29 - Sep 02, 2026

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



8-14 DAY OUTLOOK TABLE
Outlook for Aug 31 - Sep 06, 2026

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

$$