Dillon Beach, California Weather Forecast Discussion

688
FXUS66 KMTR 151052
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
352 AM PDT Mon Sep 15 2025
...New SHORT TERM, LONG TERM, AVIATION, MARINE...
.KEY MESSAGES...
Updated at 344 AM PDT Mon Sep 15 2025
- Above normal temperatures today through Wednesday
- Widespread Moderate HeatRisk today through Wednesday
- Pattern shift brings chances for elevated dry thunderstorms
   Thursday and Friday
&&
.SHORT TERM...
Issued at 344 AM PDT Mon Sep 15 2025
(Today and tonight)
A building ridge has begun to shift onshore overnight. Stratus will
continue to hug the coastline as the marine layer compresses and
weak offshore flow develops by sunrise, with low stratus mixing out
entirely by mid/late morning. Once the clouds clear, temperatures
will begin to rise above normal. Inland temperatures, especially
higher elevations will see highs ranging from the mid-80s to upper
90s, with temperatures along the immediate coast in the 70s to low
80s. Although a Heat Advisory is not necessary today, areas of
Moderate HeatRisk will make being outside for an extended period of
time uncomfortable for working or recreation. Remember to remain
hydrated with plenty of water and electrolytes, limit time outdoors
during peak heating if possible, and never leave children or pets
unattended in vehicles.
With little to no marine layer influence tonight into early Tuesday
morning, we`ll see poor RH recovery away from the direct
coastline, especially at higher elevations. The warmer overnight
lows and drier airmass will lead to accelerated drying of finer
fuels (grasses/brush) over the next few days, which will increase
fire weather concerns later this week, with more details in the
fire weather section below.
&&
.LONG TERM...
Issued at 344 AM PDT Mon Sep 15 2025
(Tuesday through Sunday)
The warmest temperatures and largest areal coverage of Moderate
HeatRisk (and small pockets of Major HeatRisk) will occur on Tuesday
with only slightly lower temperatures on Wednesday. The timing and
locations of a potential Heat Advisory for Tuesday will be made with
the afternoon update later today. While the warmer temperatures
persist through the afternoon on Wednesday, an upper level
disturbance off the coast of SOCAL begins to lift north toward the
Central Coast, bringing a large plume of moisture associated with
Tropical Storm Mario with it. As the upper level low tracks
north, we`ll see an increase in PWATs that continue to approach
200% of normal on Thursday.
As of this update, the best initial window for elevated dry
thunderstorms appears to be after midnight early Thursday through
late Thursday morning, primarily across the Central Coast in
Monterey County and southern San Benito County. Mid-level lapse
rates approach 7C/km with 30kts of shear Thursday morning, however
thermal instability is limited with MUCAPE values 

NWS MTR Office Area Forecast Discussion