071
FXUS06 KWBC 271902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Thu March 27 2025

6-10 DAY OUTLOOK FOR APR 02 - 06 2025

The ECENS and Canadian ensemble mean 500-hPa height forecasts are in good
agreement today over the forecast domain with regard to the overall synoptic
pattern over North America, but the GEFS depicts much weaker troughing over the
Great Plains than the other two ensembles, decreasing forecast confidence
particularly for the temperature outlook where model solutions differ the most.
Todays 500-hPa manual blend height forecast depicts strong ridging over the
Bering Sea, troughing and negative height anomalies over Alaska and extending
over the western CONUS and Northern Plains, and positive height anomalies over
the eastern CONUS, with the largest height departures (+150m) over the
Mid-Atlantic.

Above normal temperatures are favored over much of the southern and eastern
CONUS associated with predicted moderate anomalous ridging. Probabilities
favoring above normal temperatures exceed 80% over much of the southeastern
CONUS. Below normal temperatures are favored over much of the western CONUS,
with enhanced probabilities (>60%) for much of the West Coast and Great Basin
with persistent onshore flow and enhanced precipitation depicted by most
forecast tools. Enhanced probabilities of below normal temperatures are also
indicated for portions of New England, associated with a mean trough predicted
to be centered near northeastern Canada. For Alaska, above normal temperatures
are favored over the Aleutians in response to the strong Bering Sea ridge. In
contrast, below normal temperatures are favored over the rest of the state due
to predicted increasing easterly surface flow. In Hawaii, above normal
temperatures are strongly favored based on a consolidation of tools and the
autoblend.

Above normal precipitation is favored across most of the CONUS during the 6-10
day outlook period. In the West, this is attributed to mid-level troughing and
enhanced onshore flow. Forecast tools broadly indicate onshore flow with
enhanced moisture transport into the West Coast, favoring above normal
precipitation for much of the western CONUS, with >50% probabilities from Great
Basin westward, with >60% chances indicated for southern California. East of
the Continental Divide, increasing Gulf moisture associated with the return
flow around a surface anticyclone predicted off the Southeast coast and a
series of disturbances moving across the Ohio Valley favors above normal
precipitation for most of the Central and Eastern CONUS, particularly for
portions of the Ohio Valley and Great Lakes region (>50% probability) with a
surface low transiting the region during the forecast period. Near normal
precipitation is favored for much of Florida, likely too far removed from
large-scale storm track. In Alaska, most precipitation tools favor above normal
precipitation across all but southwestern portions of the state, where near
normal precipitation is favored. In Hawaii, odds go from a slight tilt towards
above normal precipitation for northwestern islands to near normal
precipitation for the Big Island, based on a consolidation of tools and the
autoblend.

The official 6-10 day 500-hPa height blend consists of 34% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 33% 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: Below average, 2 out of 5. Large
spread among models with regard to overall synoptic picture as well as the
placement and intensity of individual features.

8-14 DAY OUTLOOK FOR APR 04 - 10 2025

Unlike the 6-10 day period, the GEFS and Canadian models are in reasonable
agreement regarding the week-2 mean circulation pattern, but the ECMWF builds a
strong blocking ridge over northern Canada, resulting in greater spread among
forecast tools and decreased forecast confidence. The synoptic picture for
North America during week-2 as depicted by the ECMWF, GEFS, and Canadian
ensembles is similar to the 6-10 day period, with the most notable changes
being a decrease in amplitude for both the ridge over the Bering Sea and the
trough over the West Coast, as well as a weakening of positive height anomalies
over the eastern CONUS.

With a persistent synoptic pattern over North America, the week-2 temperature
outlook is very similar to the 6-10 day period. Above normal temperatures are
favored for most of the CONUS east of the Rockies as ridging over the
Mid-Atlantic though weakened remains in place, with near normal temperatures
favored only for Maine. Probabilities continue to exceed 60% for portions of
the southeastern CONUS. A slight tilt toward below normal temperatures remains
over much of the western CONUS under continued moist onshore flow. In Alaska, a
weakening of the ridge over the Bering Sea allows for increased easterly
surface flow, tilting the odds towards below normal temperature for most of the
state, with the exception of the western Aleutians, where the lingering ridge
favors above normal temperatures. With continued positive SST anomalies in the
region, Hawaii continues to be strongly favored for above normal temperatures.

With a persistence of synoptic features during the week-2 period, the
precipitation outlook is also very similar to the 6-10 day period. With
increasing spread in model solutions probabilities of above normal
precipitation over the CONUS are generally weaker, especially over the West
Coast. Near normal precipitation is favored over portions of the West Coast and
the Florida Peninsula under positive height anomalies. In Alaska, as ridging
over the Bering Sea weakens, increased available moisture from the Gulf of
Alaska tilts the odds towards above normal precipitation for the eastern
Mainland and Southeast Alaska, and near normal precipitation for the western
Mainland, the Alaska Peninsula and Aleutians. Above normal precipitation is
slightly favored for all of Hawaii, based on a consolidation of tools and the
autoblend.

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: Below average, 2 out of 5. Large
spread among models with regard to overall synoptic picture as well as the
placement and intensity of individual features.

FORECASTER: Daniel Barandiaran

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
April 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:
20030329 - 20040320 - 19900410 - 19890405 - 19690329


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:
20040320 - 20030328 - 19900409 - 19890407 - 19690328


6-10 DAY OUTLOOK TABLE
Outlook for Apr 02 - 06 2025

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



8-14 DAY OUTLOOK TABLE
Outlook for Apr 04 - 10 2025

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

$$