564
FXUS07 KWBC 301900
PMD30D
Prognostic Discussion for Monthly Outlook
NWS Climate Prediction Center College Park MD
300 PM EDT Mon Jun 30 2025


30-DAY OUTLOOK DISCUSSION FOR JULY 2025

The update to the July 2025 temperature and precipitation outlooks is based on
the latest evaluation of boundary conditions that include near-coastal sea
surface temperatures (SSTs) and surface moisture changes in both the soil and
vegetation. The latest dynamical model guidance for the short-, medium-,
extended- and subseasonal-range is utilized to adjust the mid-month outlook as
well as monthly integrated forecasts from the CFS and other available S2S
models.



The most recent model guidance across time scales maintains high odds for
monthly mean above-normal temperatures for much of the western contiguous U.S.
Substantially below-normal near coast SSTs leads to a forecast of
"Equal-Chances" or (EC) for the immediate near coastal areas of California.
Indications at the end of the month for a robust monsoon circulation and
potential heavy rainfall during periods of the first two weeks of July. This
has led to the lowering the probabilities of above-normal temperatures somewhat
for the Southwest. Model guidance supports slight increases in chances for
above-normal temperatures for the north-central U.S., Great Lakes, Northeast
and mid-Atlantic.



Below- and near-normal precipitation along with extreme heat in many areas
during the last 7-10 days in the central Plains, central Mississippi Valley,
mid-south and Southeast has substantially depleted the large anomalies of
enhanced surface wetness in the region via both soil evaporation and
transpiration. With these changes along with the dynamical model guidance
consistent with a more dry and likely warmer surface, the outlook now favors
(slightly tilted) above-normal temperatures where EC was previously forecast.



Little or no rainfall is forecast the next 7 days and with potential extreme
heat returning to Texas the odds for above-normal temperatures for much of
Texas are increased from the mid-June outlook.



Only slight changes are made for the state of Alaska. These include the removal
of favored above-normal temperatures for Southeast Alaska, the addition of
elevated odds for above-normal temperatures for the northwest part of the state
and a shift southward of favored below-normal temperatures for the southwest
coast.



For the precipitation outlook, forecast uncertainty has increased with the
update at the end of the month, which is somewhat unusual. High variability in
dynamical model guidance predictions of monthly total precipitation amounts is
evident for much of CONUS then at mid-month - especially for the central CONUS.
With this the case, the one highlighted area of favored below-normal
precipitation is separated into regions where the strongest signals remain and
are most consistent with model guidance and/or long-term precipitation trends.
The areas include the Pacific Northwest and northern Rockies, parts of the
central Plains and south Texas.



The above-normal precipitation region along the eastern seaboard remains
largely unchanged except for EC now forecast along the immediate Atlantic
coastal areas from Florida to North Carolina and less west side coverage. As
noted above, the potential for an enhanced Southwest monsoon during periods of
the first half of July support the forecast of favored above-normal
precipitation for parts of Arizona and New Mexico. For Alaska, the outlook
remains basically unchanged.



*****************************************************************************

******           Previous discussion from mid-month release            ******


*****************************************************************************



The July 2025 temperature and precipitation outlooks are primarily based on a
combination of dynamical model guidance [both Week 3-4 and integrated monthly
(North American Multi-Model Ensemble (NMME), Copernicus multi-model ensemble
system (C3S))], statistical forecast guidance, and current surface conditions.
Although there has been considerable coherent subseasonal tropical variability
in the form of atmospheric Kelvin wave activity, the Madden-Julian Oscillation
(MJO) has weakened substantially from its state in late May and early June.
Moreover, forecasts of the MJO over the next few weeks do not predict any
clear, reliable strengthening of the signal and so the MJO does not play a role
in preparation of the July outlooks. Current land surface states such as
anomalous soil moisture did contribute considerably to the outlooks for the
upcoming month.



The temperature outlook favors above-normal monthly mean temperatures for the
western half of the contiguous U.S. as well as eastward across the northern
Plains, upper Mississippi Valley, Great Lakes, and Northeast. Above-normal
temperatures are also favored along the Gulf coast, including all of Florida,
and for Southeast Alaska. Probabilities are greatest for the western U.S. where
warmer than normal conditions are overwhelmingly favored by both dynamical and
statistical model guidance, long-term positive temperature trends, and drier
than normal surface conditions in many areas. The odds for above-normal
temperatures across the northern tier of the U.S. from the Plains to the
Northeast are lower due to somewhat less agreement in model guidance and
varying surface conditions.



Warmer than normal sea surface temperatures (SSTs) and some forecast tools
favor a slight tilt toward above-normal temperatures for the Gulf coast and
Florida.



Ocean surface temperatures and potential weak ridging in dynamical model
guidance elevates odds slightly for warmer than normal temperatures in
proximity to Southeast Alaska. Alternatively, forecast troughing during the
first half of July and cooler than normal SSTs in the Bering Sea favors an area
of below-normal temperatures for a small region in Southwest Mainland Alaska.



A large area of quite wetter than normal surface conditions from frequent and
heavy precipitation events this late winter and spring were observed from the
south-central Plains eastward to the Atlantic seaboard. This is likely to
offset, to some degree, periods of warmer than normal conditions during July
and interject considerable uncertainty for the eventual July monthly mean
temperatures. So a forecast for "Equal-Chances" (EC) of either of the three
categories is forecast from the Plains eastward across the mid-South, Tennessee
Valley, lower Ohio Valley and Carolinas.



For precipitation, both dynamical and statistical model guidance, long-term
negative precipitation trends, in some areas, and drier than normal surface
conditions support elevated odds for below-normal July monthly total
precipitation amounts for the Pacific Northwest, northern Rockies and the
northern and central Plains. The most likely area for drier than normal
conditions is for parts of Montana, Idaho and Wyoming.



Forecast troughing during the first half of July centered in the Bering Sea
supports elevated odds for above-normal precipitation for much of western
Mainland Alaska. The majority of NMME and C3S monthly precipitation forecasts
are consistent with this wet signal.



Long-term positive precipitation trends and NMME and C3S monthly dynamical
model guidance favor above-normal precipitation for the Southeast, Ohio Valley,
mid-Atlantic and much of the Northeast. Probabilities are modest overall for
this region.



Large variability from both dynamical and statistical model guidance and quite
unusual late Spring temperature and precipitation conditions, makes the
forecast for the Southwest monsoon region highly uncertain. Given this, the
most appropriate forecast in this area for July 2025 is EC as either of the
three categories are equally likely given the above information at this point
in mid-June.

FORECASTER: Jon Gottschalck

The climatic normals are based on conditions between 1991 and 2020, following
the World Meteorological Organization convention of using the most recent 3
complete decades as the climate reference period.  The probability anomalies
for temperature and precipitation based on these new normals better represent
shorter term climatic anomalies than the forecasts based on older normals.

The next monthly outlook...for Aug ... will be issued on Thu Jul 17 2025

These outlooks are based on departures from the 1991-2020 base period.
$$