Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
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FXUS06 KWBC 301931
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Thu July 30 2026
6-10 DAY OUTLOOK FOR AUG 05 - 09 2026
The 0Z European ensemble (ECENS), 6z GEFS, and 0z Canadian ensemble (CMCE) mean
forecasts are in decent agreement on the average large-scale circulation
pattern over North America for the 6-10 day period, with some differences in
the pattern evolution with time. The models predict a 500-hPa ridge and
positive height anomalies over the Bering Sea that extend northward west of
Mainland Alaska. To the east, the period starts off with mid-level troughing
and near normal 500-hPa heights over much of Mainland Alaska. The ECENS mean is
deeper with this feature than the GEFS mean, with the CMCE appearing to split
the difference. The official forecast favors a blend of the ensemble means,
leaning toward the ECENS which is more consistent with yesterday`s runs. In any
case, this trough lifts northeastward and dissipates, leaving broadly
above-normal heights across the state by the end of the period. Meanwhile, an
entrenched mid-level ridge is expected to be centered over the Four Corners
Region at the start of the period, with a height maximum of 595-596 dm forecast
by the ensemble means. The closed 594-dm contour stretches a bit farther
east-southeast than yesterday, reaching the southeastern Great Plains or
adjacent Lower Mississippi Valley in the ensemble means. This feature continues
to gradually expand eastward and may slightly weaken with time, so that by the
end of the period, the CMCE and GEFS means feature a height maximum of 593 dm
centered over the east side of the Four Corners Region, with a broad and flat
mid-level ridging extending eastward through the central CONUS. The ECENS mean
remains slightly more amplified, depicting a height maximum of 595 dm at the
end of the period in a configuration that more closely resembles yesterday`s
forecasts, with less broadening to the east. The official forecast is a blend
that leans toward the ECENS, which is a little more consistent with yesterday`s
solution. Farther east, a mid-level trough in central Canada pushes
southeastward, lowering heights toward normal over the Northeast. The CMCE is
most amplified with this feature, bringing 500-hPa heights down to 6 dm or more
below normal in the extreme northeastern CONUS at the end of the period. The
ECENS and GEFS means are less amplified, forecasting near-normal 500-hPa
heights at the end of the period, and approximate the preferred solution more
consistent with model runs from the past few days..
With above-normal 500-hPa mean heights anticipated across the entire CONUS, the
forecast likewise favors above-normal temperatures across the entire CONUS. The
best chances for above normal temperatures (over 70 percent) are near the
center of the mid-level ridge axis stretching from Utah southeastward into the
south-central Great Plains. Chances for abnormal warmth exceed 50 percent
across the bulk of the CONUS, with lower odds limited to the northern tier of
the CONUS from the Great Lakes to the Pacific Northwest, and to southern
Arizona where monsoonal moisture and thundershower activity are expected to
limit daytime heating. Temperatures are expected to be considerably above
normal in the Northeast as the period gets underway, but should drop closer to
normal in conjunction with the 500-hPa height falls expected by the end of the
period. Farther north, above-normal temperatures are also expected across most
of central and southeastern Alaska under rising heights, but part of the far
northwestern Mainland have nominally elevated chances for below normal
temperatures, partially driven by anomalously low sea surface temperatures and
ice coverage in adjacent offshore waters. Meanwhile, weak 500-hPa ridging is
expected across Hawaii, along with abnormally high sea surface temperatures,
especially near the Big Island. This favors above normal temperatures
statewide, with chances increasing from near 40 percent across Kauai and Niihau
in the northwest to more than 80 percent on the south side of the Big Island.
Subnormal precipitation is favored around the northern and eastern sides of the
mid-level ridge centered over the Four Corners Region under broadly
anticyclonic mid-level flow. Chances for below normal totals exceed 50 percent
across eastern Oregon and adjacent Idaho, and drier than normal weather is at
least marginally favored across the northern Rockies and most of the northern
and central Plains. Closer to the ridge center, the pattern is favorable for
significant incursions of tropical moisture into lower parts of the Southwest,
especially southern Arizona, where chances for above-normal precipitation
exceed 50 percent. The forecast is more uncertain farther east, where guidance
is not as consistent and ensemble-derived tools are unremarkable. In aggregate,
the tools marginally favor above normal precipitation from the Mid-Atlantic and
Lower Great Lakes through the Northeast, and this is reflected in the forecast.
Guidance also tilts toward above-normal precipitation across much of northern
and eastern Alaska while subnormal amounts are slightly favored over
southwestern parts of Mainland Alaska, consistent with a blend of the
Consolidation, analogs, and the ECENS raw and reforecast precipitation output.
In Hawaii, there is a slight tilt of the odds toward above-normal temperatures
statewide, consistent with the Consolidation and a blend of model guidance
leaning toward the ECENS mean.
The official 6-10 day 500-hPa height blend consists of 15% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 15% of Today`s 6z GFS Ensemble Mean centered
on Day 8, 50% of Today`s 0z European Ensemble Mean centered on Day 8, and 20%
of Today`s operational 0z ECMWF centered on Day 8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Average, 3 out of 5, due to decent
model agreement on the predicted 500-hPa height pattern, offset by some
inconsistency in the derived temperature and precipitation tools and increasing
uncertainty in the evolution of the 500-hPa pattern late in the period.
8-14 DAY OUTLOOK FOR AUG 07 - 13 2026
Ensemble mean forecasts for the 8-14 day period all predict a similar mid-level
circulation pattern to the 6-10 day period forecast, with some eastward
expansion or progression of the western CONUS mid-level ridge. After some
deamplification and broadening of the ridge early week-2, ensemble means agree
that some degree of reamplification is expected. The details of this pattern
evolution are uncertain with the models in fair agreement at best on the exact
timing of the reamplification and the eventual locations of the 500-hPa height
maximum and the mid-level ridge axis. North and east of the mid-level ridge
center, the models all agree on a more pronounced mid-level trough impacting
the northeastern CONUS relative to yesterday, with the manual blend now showing
below normal mean week-2 500-hPa heights. The CMCE is most robust with this
feature, but the less amplified ECENS and GEFS means are favored, being more
consistent with yesterday`s runs. This eventually results in a pattern with
some degree of mid-level troughing over at least part of the eastern or
east-central CONUS, but evolution, location, and strength of this feature are
uncertain due to significant model disparity.
Above normal temperatures are expected to continue across a vast majority of
the CONUS under the influence of mid-level ridging and broadly above-normal
500-hPa heights. The best week-2 chances for abnormal warmth (60 to 70 percent)
extend from the east-central Rockies through much of the central and southern
Great Plains, the Lower Mississippi and Tennessee Valleys, and the Southeast.
This represents an eastward displacement from the 6- to 10-day forecast,
consistent with the expected reamplification and reorientation of the mid-level
ridge. The likelihood of above normal week-2 temperatures decreases to the
north and northeast under the influence of the encroaching mid-level trough,
with near normal mean temperatures favored in areas closest to this feature
across the northern Great Lakes and upper Northeast. The forecast of robust
monsoonal rainfall, especially in the Southwest, lowers the odds for abnormal
warmth there as well, with chances ranging from 40 to 50 percent there. Warmer
than normal conditions remain nominally favored from central through
southeastern Alaska, with below normal temperatures somewhat more likely across
the northern tier of the state adjacent to colder than normal sea surface
temperatures and relatively extensive ice coverage in offshore waters. Across
Hawaii, weak mid-level ridging and above-normal sea surface temperatures are
expected, particularly near the Big Island, favoring above normal temperatures.
The likelihood of abnormal warmth again exceeds 80 percent on part of the Big
Island.
The expected evolution of the mid-level ridge favors an increasingly strong
monsoonal circulation, with the reforecast ECENS precipitation output being the
most robust with this signal. The forecast again significantly favors wetter
than normal conditions in the Southwest, with increased chances for surplus
precipitation stretching farther north than during the 6-10 day period, through
southern Idaho, western Wyoming, and adjacent Montana. The likelihood of above
normal amounts exceeds 50 percent near from the lower Colorado river basin
northward and eastward through southeastern Nevada, southwestern Utah, and most
of Arizona. Farther east, the increasing influence of the mid-level ridge in
the central CONUS favors below normal precipitation through the Plains, with
the best odds (over 40 percent) stretching from the lower Rio Grande River
northward through central sections of Texas, most of Oklahoma and Kansas, and
adjacent sections of Nebraska, Missouri, and Arkansas. The ECENS, CMCE, and
GEFS means all show less than 0.25 of precipitation falling on the southern
half of this region during week-2, and the Consolidation depicts higher odds
for dryness over the northern half than elsewhere. Farther east, the tools show
weak signals and are in fair agreement nominally favoring above normal
precipitation in the eastern CONUS adjacent to Canada. Dryness is marginally
favored across central and southern Florida under the influence of a waxing
subtropical ridge, and in the Pacific Northwest where lower 500-hPa heights are
encroaching on the evolving mid-level ridge farther east. Using a blend of the
guidance leaning in the direction of the Consolidation and the raw and
reforecast ECENS precipitation output, below normal precipitation is nominally
favored along the western tier of Mainland Alaska while the odds tilt slightly
toward surplus precipitation in part of the northeastern Mainland. Hawaii also
has slightly enhanced chances for above normal precipitation, consistent with
the Consolidation and the raw ECENS forecast.
The official 8-14 day 500-hPa height blend consists of: 20% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 20% of Today`s 6z GFS Ensemble Mean centered
on Day 11, 50% of Today`s 0z European Ensemble Mean centered on Day 11, and 10%
of Today`s 0z Canadian Ensemble Mean centered on Day 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Average at best, 3 out of 5, with
adequate model agreement on the mean 500-hPa height pattern, offset by the
uncertainties inherent to an evolving summertime pattern and differences among
temperature and precipitation tools.
FORECASTER: Rich Tinker
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:
20010805 - 19930730 - 20080729 - 20170728 - 20220713
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:
20030711 - 20010805 - 20140724 - 20250727 - 20220713
6-10 DAY OUTLOOK TABLE
Outlook for Aug 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 A IDAHO A B NEVADA A B
W MONTANA A B E MONTANA A B WYOMING A B
UTAH A N ARIZONA A A COLORADO A N
NEW MEXICO A N N DAKOTA A B S DAKOTA A B
NEBRASKA A B KANSAS A B OKLAHOMA A B
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 A N
INDIANA A N OHIO A N KENTUCKY A N
TENNESSEE A N ALABAMA A N NEW YORK A A
VERMONT A A NEW HAMP A A MAINE A A
MASS A A CONN A A RHODE IS A A
PENN A A NEW JERSEY A A W VIRGINIA A A
MARYLAND A A DELAWARE A A VIRGINIA A A
N CAROLINA A N S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A A AK N SLOPE N A
AK ALEUTIAN B B AK WESTERN N N AK INT BSN N A
AK S INT N N AK SO COAST N N AK PNHDL N N
8-14 DAY OUTLOOK TABLE
Outlook for Aug 07 - 13 2026
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A N NRN CALIF A N
SRN CALIF A A IDAHO A A NEVADA A A
W MONTANA A N E MONTANA A N WYOMING A A
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A A N DAKOTA A B S DAKOTA A B
NEBRASKA A B KANSAS A B OKLAHOMA A B
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA A B IOWA A B MISSOURI A B
ARKANSAS A B LOUISIANA A B WISCONSIN A B
ILLINOIS A B 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 N N NEW HAMP N N MAINE N 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 B AK N SLOPE N N
AK ALEUTIAN N B AK WESTERN N B AK INT BSN A N
AK S INT A N AK SO COAST A N AK PNHDL N N
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.
$$