759
FXUS21 KWNC 121802
PMDTHR
US Hazards Outlook
NWS Climate Prediction Center College Park MD
300 PM EDT June 12 2026

SYNOPSIS: Mid-level high pressure predicted over the Carolinas and Florida
increases chances for extreme heat early and throughout the period
respectively. Mid-level high pressure is then forecast to build into the Great
Plains and West with time, increasing chances for extreme heat in parts of the
Central and Southern Plains by the middle and end of week-2. A stationary
surface front across the Middle Mississippi, Ohio, and Tennessee Valley brings
elevated chances for heavy precipitation. Early in the period, strong winds are
possible across parts of the Rockies and Great Plains.

HAZARDS

Moderate risk of extreme heat for the central and southern Florida Peninsula,
Sat-Tue, Jun 20-23.

Slight risk of extreme heat for the entire Florida Peninsula, Sat-Fri, Jun
20-26.

Slight risk of extreme heat for portions of the Southeast and southern
Mid-Atlantic, Sat-Mon, Jun 20-22.

Slight risk of extreme heat for much of the Southern Plains and Central Plains,
Mon-Fri, Jun 22-26.

Slight risk of heavy precipitation for the Middle Mississippi, Ohio, and
Tennessee Valleys and adjacent areas, Sat-Mon, Jun 20-22.

Slight risk of high winds from the central and southern High Plains westward
across much of the Rockies, and central and southern portions of the Great
Basin, Sat-Mon, Jun 20-22.

DETAILED SUMMARY

FOR MONDAY JUNE 15 - FRIDAY JUNE 19:
https://www.wpc.ncep.noaa.gov/threats/threats.php

FOR SATURDAY JUNE 20 - FRIDAY JUNE 26: Over the Southeast and Gulf Coast
subtropical ridging is anticipated to persist through much of the week-2
period. This feature is favored to contribute towards areas of extreme heat.
Bias-corrected GEFS and ECENS Heat Index guidance for week-2 depicts values
near or above 105 deg F across both of these regions. The National Blend of
Models (NBM) predicts near-record or record high nighttime minimum temperatures
across much of the Florida Peninsula during this time, ranging from about 75-85
deg F. The Weather Prediction Center (WPC) Probabilistic HeatRisk tool
highlights elevated chances of major HeatRisk across the region.  A moderate
risk of extreme heat is designated for the central and southern Florida
Peninsula, Jun 20-23, and a slight risk of extreme heat is posted for the
entire Florida Peninsula throughout the duration of week-2. A second slight
risk area is depicted for much of the Southeast Georgia and Coastal Carolinas,
Jun 20-22 with mid-level troughing anticipated to moderate temperatures by the
second half of week-2.



Another area of favored extreme heat includes the Great Plains from southern
Nebraska to the Rio Grande Valley in Texas, coincident with the forecast
expansion of the subtropical ridge into these areas. This represents an
increase in spatial coverage of extreme heat relative to yesterday.
Probabilistic Extremes Tools (PETs) guidance and week-2 heat index guidance
indicate actual air temperatures in the mid to upper 90s in these areas, and
heat index values at or above 105 deg F, due to dew point temperatures well up
into the 60s and low 70s. Dynamical model guidance indicates the ridge over the
Southern and Central Plains is more likely to expand westward across the
Rockies and into the Intermountain West rather than amplify northward across
the Northern Plains. Tools have trended in this direction today with the
mid-level ridge axis further West relative to yesterday. Therefore, a slight
risk of extreme heat is posted for Jun 22-26 from the Rio Grande into the
central High Plains.



During week-2, a stationary front is forecast across parts of the Middle
Mississippi, Ohio, and Tennessee Valleys. This may drive thunderstorm clusters
(Mesoscale Convective System) forecast to move across the central and
east-central CONUS. A slight risk of above-normal precipitation is most
warranted from Jun 20-22 over a broad portion of the east-central CONUS, where
PET guidance shows precipitation values in excess of the 85th percentile of the
historical distribution and greater than 1-inch. The ECENS and GEFS PETs are in
good agreement today on the predicted location of the heaviest precipitation.
Enhanced low-level Gulf moisture streaming northward from the Gulf Coast could
provide the fuel necessary for precipitation and thunderstorm activity. Though
no specific flooding areas are designated on today`s map, any slow-moving or
stalled thunderstorms could result in localized flooding and potentially
hazardous conditions.



A series of surface lows across the West early in week-2 support a slight risk
of periods of high winds for parts of the Interior West, Rockies, and High
Plains, Jun 20-22. The ECENS PET indicates at least a 20% chance of many of
these areas exceeding the 85th percentile and uncalibrated ECENS and GEFS
ensembles showing enhanced probabilities of wind gusts ranging from 20-35 mph,
locally greater. Gusty wind speeds may enhance wildfire risk especially across
parts of the Four Corners region and the Southwest, where the National
Interagency Fire Center indicates a moderate risk of significant fire potential
by the end of week-1 and where there are currently active fires.

FORECASTER: Ryan Bolt

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