Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
249 PM EDT Mon Jun 15 2026

Valid 00Z Tue Jun 16 2026 - 00Z Thu Jun 18 2026

...Increasing threat of significant heavy rainfall from South Texas to the
lower Mississippi Valley through the next couple of days...

...Cooler air surges into the eastern two-thirds of the country...

...Heat across the Pacific Northwest will begin to moderate on Tuesday...

A weather pattern favoring cold air intrusions from Canada is bringing a
refreshingly cool airmass into much of the eastern two-thirds of the
country.  In the post-frontal airmass, morning temperatures in the 40s and
50s will spread from the Northern Tier to the Northeast by tomorrow
morning. Daytime high temperatures will only recover to the 70s and lower
80s, which are more than 10 degrees below normal for portions of those
areas.

While the cool air mass dominates the weather pattern across much of the
central and eastern U.S., the forecast remains on track for a prolonged
heavy rainfall event from South Texas through the Lower Mississippi
Valley. This is in response to complex interactions among an upper-level
disturbance exiting the Mexican plateau, tropical moisture near the
western Gulf and northeastern Mexico, and the same cold front becoming
nearly stationary near the Gulf Coast. Through the next 3 days, storm
total rainfall of 5-7" with locally higher amounts can be expected along
the Texas coastline into Louisiana. Numerous instances can be expected
through Wednesday in this area, some of which could be significant. In
addition, the National Hurricane Center continues to monitor this area of
disturbed weather for tropical cyclone development near the Texas Gulf
Coast later this week, although uncertainty remains with how this system
will evolve.

Across the Northern Tier, a couple of quick-moving low pressure systems
will deliver showers and gusty winds through the next couple of days.  The
first system will move from the Northern Plains today to the Great Lakes
on Tuesday. The second system is forecast to be the stronger of the two,
and will be intensify over the Northern Plains Wednesday morning, bringing
with it the chance of widely scattered severe weather and flash flooding
to the Midwest.

Elsewhere, monsoonal showers and embedded thunderstorms from the Four
Corners to the Southern Rockies today should have taper off tomorrow.
Across the Pacific Northwest, heat is forecast to peak today with
record-high temperatures reaching as high as the upper-90s before cooling
off on Tuesday.  The Desert Southwest and the Central Valley of California
will remain hot, with highs in the 110s and 90s-100s, respectively. 
Florida will see more numerous showers and thunderstorms across the
northern part of the state through the next couple of days.


Asherman/Kong


Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php