Prognostic Meteorological Discussion
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FXUS06 KWBC 021902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Wed April 02 2025

6-10 DAY OUTLOOK FOR APR 08 - 12 2025

The 0z GEFS, ECENS, and CMCE are in very good agreement regarding an amplified
500-hPa height pattern across North America. Troughing is forecast over the
eastern contiguous U.S. (CONUS), with ridging becoming established across the
western CONUS. Troughing initially forecast across central Alaska is predicted
to weaken, with ridging and positive height anomalies expanding over the state
by the end of the period. Todays manual 6-10 day 500-hPa height blend depicts
above-normal heights across much of the western CONUS, and below-normal heights
over the northeastern quadrant of the CONUS. Near-normal heights are favored
across the south-central and southeastern CONUS. Near- to slightly below-normal
heights are depicted over much of Mainland Alaska and the Alaska Peninsula,
with above-normal heights forecast over the western Aleutians, far eastern
Mainland, and Southeast Alaska.

Probabilities for below normal temperatures are increased over much of the
eastern CONUS underneath northerly mid-level flow behind a frontal boundary
predicted to move through at the outset of the period, with the highest chances
(greater than 70 percent) across the Southeast and Mid-Atlantic. There are
concerns for frosts or freezes across some areas as relatively colder
temperatures coincide with emerging vegetation. Ridging forecast across the
West favors elevated probabilities of above normal temperatures. Troughing
predicted over central Mainland Alaska supports increased chances for
above-normal temperatures over the southern and eastern parts of the state due
to enhanced southerly flow. Conversely, below-normal temperature chances are
increased on the backside of the mean trough axis across western Mainland.
Increasing mid-level heights over the Aleutians supports enhanced near to above
normal temperatures chances. Above-normal temperatures continue to be favored
across Hawaii.

A broad area of enhanced below-normal precipitation probabilities are forecast
across much of the western CONUS and building into the Great Plains, Midwest,
and Southeast as surface high pressure becomes established. A frontal system is
favored to quickly progress off the East Coast at the outset of the period
bringing a slight tilt towards above-normal to just the Eastern Seaboard.
Elevated probabilities for above-normal precipitation are favored across
eastern Alaska due to enhanced onshore flow ahead of troughing. Near to below
normal precipitation chances are increased across the  southwestern Mainland
and the Aleutians underneath a more northerly mid-level flow pattern.
Above-normal precipitation is forecast across Hawaii supported by the
consolidation forecast tool.

The official 6-10 day 500-hPa height blend consists of 40% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 40% of Today`s 0z European Ensemble Mean
centered on Day 8, and 20% 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 in the model height pattern.

8-14 DAY OUTLOOK FOR APR 10 - 16 2025

The 500-hPa height pattern predicted during week-2 is similar but less
amplified to that of the 6-10 day period, with some eastward progression of the
features. The dynamical models remain in good agreement regarding ridging
(troughing) across the western (eastern) CONUS. The week-2 manual 500-hPa
height blend depicts near to below normal heights for most areas east of the
Mississippi River, and above-normal heights upstream to the west. Weakly above
normal heights are depicted across Alaska underneath a weak trough signature
persisting across the central Mainland. Larger positive height anomalies are
forecast across the Aleutians and far western Mainland associated with ridging
centered across eastern Russia and the Bering Sea.

Below-normal temperature probabilities remain slightly favored across the
eastern third of the CONUS with higher probabilities (>40%) over portions of
the southeastern U.S. Enhanced probabilities of above-normal temperatures are
indicated across the West, especially the Four Corners (>70%), under the
forecast positive 500-hPa height departures. As the mean trough axis shifts to
the east and weakens, warming temperatures are forecast across the Plains and
Mississippi Valley resulting in an eastward  expansion of the enhanced
above-normal temperature probabilities to include these areas. Chances for
above-normal temperatures remain across southern Alaska due to continued
southerly flow. A slight tilt toward below-normal temperatures is favored over
the western Mainland. Increased probabilities for above-normal temperatures
remain forecast across Hawaii.

Ridging over the West, combined with surface high pressure over the East, favor
increased chances for below-normal precipitation over much of the CONUS, with
chances above 50 percent for portions of the Great Basin and Southern Plains.
An area of surface low pressure development along the East Coast is possible
later during the week-2 period increasing chances for near normal precipitation
along much of the Eastern Seaboard. A slight tilt toward below normal
precipitation remains favored across for southwestern Mainland Alaska
underneath slightly enhanced northerly mid-level flow. Near normal is favored
for much of the rest of the mainland associated with weak troughing across the
Central Mainland. Above-normal precipitation chances are increased across
Hawaii.

The official 8-14 day 500-hPa height blend consists of: 10% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 20% 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: About Average, 3 out of 5, Good
agreement among the dynamical guidance is offset by a progressive pattern.

FORECASTER: Ryan Bolt

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:
19630404 - 19650416 - 19970313 - 19670314 - 20030331


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:
20030330 - 19630404 - 19670317 - 19650415 - 19970312


6-10 DAY OUTLOOK TABLE
Outlook for Apr 08 - 12 2025

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



8-14 DAY OUTLOOK TABLE
Outlook for Apr 10 - 16 2025

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

$$