399
FXUS06 KWBC 181902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Wed June 18 2025

6-10 DAY OUTLOOK FOR JUN 24 - 28 2025

Today`s model solutions are in good agreement on the predicted 500-hPa
circulation pattern across North America and surrounding regions during the
6-10 day period. The manual 500-hPa height blend is based primarily on the
ensemble means from the GEFS, ECMWF and Canadian models. The resultant manual
blend features a fairly amplified pattern with widespread ridging over the
North Pacific and Chukchi Sea and weak troughing over the Bering Sea, deeper
troughing over the western Contiguous U.S. (CONUS), and strong ridging over
much of the eastern CONUS. Model solutions de-amplify this pattern fairly
quickly during the 6-10 day period and have been consistently doing so for the
last several days, increasing confidence in this transition. However, model
solutions diverge during week-2 after this predicted transition, making for
less forecast certainty later in the forecast period.

As a result of continued troughing over the West Coast and increased cloudiness
due to influxes of tropical moisture, below-normal temperatures continue to be
favored over much of the southwestern CONUS and along the Rio Grande Valley.
Probabilities of below-normal temperatures exceed 50% for portions of the
Desert Southwest where the cooling influence of cloud cover is likely to be
greatest. Above-normal temperatures are strongly favored east of the
Mississippi, with probabilities exceeding 80% for portions of the Ohio Valley,
Appalachians, Mid-Atlantic, and Northeast U.S. with amplified ridging forecast
over the southeastern CONUS. Above-normal temperatures are also favored for
much of the Southern and Central Plains, while near-normal temperatures are
most likely for the Northern Plains and portions of the Upper Mississippi
Valley. The Northern Rockies as well as eastern portions of Oregon and
Washington, also tilt towards above-normal temperatures, consistent with a
growing majority of forecast tools. Under predicted positive 500-hPa height
anomalies, above-normal temperatures are likely over northeastern Alaska, while
below-normal temperatures are favored for the Aleutians and much of southern
Alaska, consistent with model depictions of strengthening troughing over the
Bering Sea. Above-normal temperatures are favored for Hawaii, with positive
surrounding sea surface temperature anomalies.

A strong Bermuda high is depicted in model ensembles throughout the forecast
period, resulting in a steady stream of Gulf moisture advecting into the Great
Plains and Southeast U.S., as well as tropical moisture streaming north into
the western CONUS from the Eastern Pacific, favoring above-normal precipitation
for much of the CONUS. Probabilities of above-normal precipitation are elevated
(>50%) over the Upper Mississippi Valley with support from the upper-level
trough over the West, and also across much of the Rio Grande Valley, Southwest,
and Southern Rockies (>50%), where models depict converging moist airmasses
from the Gulf to the east, and from the west as a result of tropical cyclone
activity in the Eastern Pacific. Near-normal precipitation is favored along
portions of the East Coast, due to the strong Bermuda high offshore reducing
instability along the coast. Over Alaska, with persistent easterly flow at the
surface and as the upper-air pattern switches from ridging to troughing over
the course of the 6-10 day period, the odds tilt weakly towards above-normal
precipitation for most of the state, with slightly higher probabilities (>40%)
for the Alaskan Interior. For the Hawaiian Islands, elevated odds (>50% for all
except the Big Island) of above-normal precipitation are favored, consistent
with the Hawaii CON and Autoblend.

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. Very
good agreement among the temperature and precipitation dynamical and
statistical tools is offset by diverging model solutions late in the period.

8-14 DAY OUTLOOK FOR JUN 26 - JUL 02, 2025

Ensemble mean solutions for the 8-14 day period predict a continued
de-amplification of the 500-hPa circulation pattern that began during the 6-10
day period across North America and the surrounding regions. Both the troughing
along the West Coast and positive height anomalies over the eastern CONUS are
weaker in week-2, resulting in close to zonal flow over North America. Weak
troughing is favored to continue over the Bering Sea, while ridging over the
North Pacific remains firmly in place.

Above-normal temperatures continue to be favored across the eastern half of the
CONUS in the week-2 period, under continued ridging and positive 500-hPa height
anomalies. Probabilities are slightly weaker than the 6-10 day period likely
due to de-amplification of the East Coast ridge but still exceed 60% for
portions of the Mid-Atlantic. Weaker troughing over the western CONUS leads to
a quick erosion of the widespread below-normal temperatures favored in the 6-10
day period west of the Continental Divide. In week-2 below-normal temperatures
are only weakly favored for the Desert Southwest and along the West Coast,
while above-normal temperatures become most likely for much of the interior
northwestern CONUS. In Alaska, a slight tilt towards above-normal temperatures
remains for the North Slope under continued positive 500-hPa height anomalies,
while below-normal temperatures become slightly more favored (>40%) for
southern and western portions of the state as the weak trough over the Bering
Sea moves slightly closer to the western coast. Hawaii continues to lean
towards above-normal temperatures, supported by the Hawaii CON.

Odds tilt towards above-normal precipitation for most of the CONUS due to
continued availability of tropical moisture from both the Gulf region as well
as the Eastern Pacific. Probabilities of above-normal precipitation are
slightly enhanced for portions of the Rio Grande Valley and Southwest, as well
as for portions of the Upper Mississippi Valley and western Great Lakes where
model ensembles indicate an increased potential for convective weather. A
weakly building trough over the Bering Sea tilts Alaska towards above-normal
precipitation. Above-normal precipitation also continues to be weakly favored
for the Hawaiian Islands.

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: About average, 3 out of 5. Good
agreement among the temperature and precipitation dynamical and statistical
tools is offset by diverging model solutions as the period progresses.

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
June 19.


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:
20000606 - 20010629 - 19780610 - 20060619 - 20010620


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:
20010630 - 20060618 - 20000605 - 20010620 - 19780609


6-10 DAY OUTLOOK TABLE
Outlook for Jun 24 - 28 2025

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    A     OREGON      A    N     NRN CALIF   N    N
SRN CALIF   B    N     IDAHO       N    N     NEVADA      N    N
W MONTANA   A    A     E MONTANA   N    A     WYOMING     N    A
UTAH        N    A     ARIZONA     B    A     COLORADO    B    A
NEW MEXICO  B    A     N DAKOTA    N    A     S DAKOTA    N    A
NEBRASKA    N    A     KANSAS      A    A     OKLAHOMA    A    A
N TEXAS     A    A     S TEXAS     A    A     W TEXAS     B    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       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    N     DELAWARE    A    N     VIRGINIA    A    N
N CAROLINA  A    N     S CAROLINA  A    N     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  A    A
AK ALEUTIAN B    A     AK WESTERN  B    A     AK INT BSN  N    A
AK S INT    B    A     AK SO COAST B    A     AK PNHDL    B    A



8-14 DAY OUTLOOK TABLE
Outlook for Jun 26 - Jul 02, 2025

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    A     OREGON      N    N     NRN CALIF   N    N
SRN CALIF   N    N     IDAHO       A    N     NEVADA      N    N
W MONTANA   A    N     E MONTANA   A    N     WYOMING     A    N
UTAH        A    N     ARIZONA     B    A     COLORADO    A    A
NEW MEXICO  B    A     N DAKOTA    A    A     S DAKOTA    A    A
NEBRASKA    A    A     KANSAS      A    A     OKLAHOMA    A    A
N TEXAS     A    A     S TEXAS     A    A     W TEXAS     B    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       A    A
MASS        A    A     CONN        A    A     RHODE IS    A    A
PENN        A    A     NEW JERSEY  A    N     W VIRGINIA  A    A
MARYLAND    A    N     DELAWARE    A    N     VIRGINIA    A    N
N CAROLINA  A    N     S CAROLINA  A    N     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  N    N
AK ALEUTIAN B    N     AK WESTERN  B    A     AK INT BSN  B    N
AK S INT    B    A     AK SO COAST B    N     AK PNHDL    B    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.

$$