Severe Thunderstorm Warning 67, NWS Miami, FL

Area Forecast Discussion
National Weather Service Miami FL
247 PM EDT Thu Aug 20 2026

...New UPDATE...

.KEY MESSAGES...
Updated at 246 PM EDT Thu Aug 20 2026

 - Slightly lower high temperatures expected today but heat
   indices of 105-110 are still anticipated this afternoon. Heat
   Advisory in effect from 11AM to 6PM.

 - Scattered thunderstorms expected after midday this afternoon
   and into the evening will provide some relief from the heat.

&&

.UPDATE...
Issued at 246 PM EDT Thu Aug 20 2026

The forecast remains on track this afternoon with isolated showers
and thunderstorms developing along sea breeze boundaries. A
continued moistening trend is underway across the region, with the
12Z MFL sounding and recent ACARS data showing PWAT values closer to
climatological norms for mid-August (1.6-1.8 inches). Convection is
expected to increase in coverage through the afternoon and early
evening, favoring the eastern half of the peninsula under a
prevailing westerly flow. Meanwhile, increasing humidity combined
with high temperatures is maintaining Major HeatRisk conditions
across most urban areas today. Residents are encouraged to continue
exercising heat safety by staying hydrated, taking frequent breaks
in the shade or indoors, and checking on vulnerable individuals.
Shower and thunderstorm activity will gradually diminish after
sunset, with overnight lows settling into the mid-70s across the
interior while remaining a few degrees above normal closer to the
coasts.

&&

.SHORT TERM...
(Today through Friday)
Issued at 109 AM EDT Thu Aug 20 2026

As the Saharan dust continues to filter out of the area for the end
of this week, deeper moisture will simultaneously begin to work back
into South Florida for the end of the week as a couple of upper
level disturbances in the Caribbean help infiltrate extra tropical
moisture. These upper level lows are not expected to reach South
Florida, but will still provide this deeper moisture advection.
Similarly, an upper-level trough will enhance underneath strong jet
dynamics as a result of a stout ridge across the Southwestern US. As
the trough deepens and digs southwards, prevailing wind flow will
shift to more of a southerly direction across the forecast area.
This will result in a pooling of the deep moisture for the end of
this week and likely beyond.

As a result of the pattern above and the dissipation of the dust
plume, temperatures should fall closer to normal in the low to mid
90s for today and tomorrow while convection also initiates a couple
hours earlier and starts to become more widespread in the afternoon
and evening hours. Given the prevailing southwesterly flow today and
eventually southerly flow on Friday and into the weekend, the
Atlantic sea breeze will not advance as far inland as it typically
does, which is expected to result in the more widespread coverage of
showers and thunderstorms to occur across Southeast Florida. Some
storms will be capable of producing strong wind gusts as high as 40-
50 mph but severe parameters are rather limited for this end of of
week time period. Main concerns will be for heavy rainfall lowering
visibilities on roadways, strong wind gusts and localized flooding
as a result of training storms or convection re-developing over the
same locations.

In terms of heat, it should not be quite as hot as the last couple
of days given the dust plume dissipating. However, with deeper
moisture arriving there will still be dew points in the upper 70s
for most of the region and high temps achieving the low to mid 90s
prior to rain occurring across the region in the afternoon.
Therefore, opting to go with a Heat Advisory again for today from
11AM - 6PM for all of South Florida. If rainfall becomes widespread
earlier than 6PM and causes sudden decreases in heat levels, then
this advisory could be canceled prior to 6PM.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 109 AM EDT Thu Aug 20 2026

The extended period will see a much needed return to a more typical
summertime pattern. An upper level ridge will remain anchored over
the western US while the eastern US will remain under the influence
of a mid-level trough set up across most of the Eastern Seaboard
through at least early next week. Expect mainly diurnally driven sea-
breeze convection each day with seasonable PoPs (40-60%) favoring
the afternoon and early evening hours, and then widely scattered
coastal showers during the overnight period. Highest rain chances
and most widespread coverage is expected across interior South
Florida where the sea breezes and outflow boundaries collide.

Temperatures will remain above normal through the weekend and into
early next week. Max heat indices will remain around advisory
criteria each day, so additional heat headlines will remain
possible.

&&

.AVIATION...
(18Z TAFS)
Issued at 136 PM EDT Thu Aug 20 2026

Mainly VFR conditions will prevail through the period, though TEMPOs
may be needed for east coast terminals this afternoon due to
SHRA/TSRA. SE winds around 10 kts at the east coast terminals will
become L/V after 01Z. At KAPF, westerly winds will gradually
decrease overnight, then increase out of the southwest after 16Z.

&&

.MARINE...
Issued at 109 AM EDT Thu Aug 20 2026

Gentle west-northwest winds expected across the Gulf waters today
with southerly winds across the Atlantic. These winds are expected
to shift a little more southwesterly for the Gulf and southeasterly
for the Atlantic on Friday. Seas will remain at 1-2 feet or less.
Scattered showers and thunderstorms are possible late each day and
in the late night hours which may result in locally hazardous winds
and seas.

&&

.PRELIMINARY POINT TEMPS/POPS...
Miami            81  93  79  93 /  20  50  20  50
West Kendall     79  92  77  92 /  20  40  10  50
Opa-Locka        80  93  80  93 /  20  50  20  50
Homestead        79  92  78  92 /  10  30  10  40
Fort Lauderdale  81  92  80  92 /  20  50  20  50
N Ft Lauderdale  81  93  80  93 /  20  50  20  50
Pembroke Pines   81  93  80  93 /  20  50  20  50
West Palm Beach  80  94  78  93 /  10  50  20  50
Boca Raton       80  92  79  92 /  10  50  20  50
Naples           79  91  79  91 /  20  30  20  20

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory until 6 PM EDT this evening for FLZ063-066>075-168-
     172>174.

AM...None.
GM...None.
&&

SHORT TERM...Redman
LONG TERM....Redman
AVIATION...DPB

Preliminary Local Storm Report
National Weather Service Miami FL
132 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0637 PM     Wildfire         5 SE Rotenberger Wildli 26.36N 80.76W
08/19/2026                   Palm Beach         FL   Park/Forest Srvc

            The H1 (50) Wildfire has burned 9733 acres
            and is at 95 percent contained.

&&

BNB

Preliminary Local Storm Report
National Weather Service Miami FL
327 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0316 PM     Wildfire         5 N Pa-Hay Okee Overlo  25.50N 80.79W
08/20/2026                   Miami-Dade         FL   Park/Forest Srvc

            The Movie Dome wildfire in the Everglades
            has burned an estimated 2,000-3,000 acres.

&&

DPB

Special Weather Statement
National Weather Service Miami FL
414 PM EDT Thu Aug 20 2026

FLZ067-068-168-202045-
Coastal Palm Beach County FL-Inland Palm Beach County FL-
Metro Palm Beach County FL-
414 PM EDT Thu Aug 20 2026

...A strong thunderstorm will impact portions of northeastern Palm
Beach County through 445 PM EDT...

At 413 PM EDT, National Weather Service meteorologists were tracking
a strong thunderstorm near North County Airport, or 7 miles northwest
of Palm Beach Gardens. This storm was nearly stationary.

HAZARD...Wind gusts of 45 to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
West Palm Beach, Jupiter, Palm Beach Gardens, North County Airport,
The Acreage, Caloosa, Philo Farms, Jupiter Farms, and Limestone
Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

&&

LAT...LON 2678 8015 2680 8039 2696 8038 2696 8014
TIME...MOT...LOC 2013Z 252DEG 3KT 2690 8028

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

GR

Special Weather Statement
National Weather Service Miami FL
445 PM EDT Thu Aug 20 2026

FLZ067-068-168-202115-
Coastal Palm Beach County FL-Inland Palm Beach County FL-
Metro Palm Beach County FL-
445 PM EDT Thu Aug 20 2026

...A strong thunderstorm will impact portions of northeastern Palm
Beach County through 515 PM EDT...

At 445 PM EDT, National Weather Service meteorologists were tracking
a strong thunderstorm near North County Airport, or near Palm Beach
Gardens. This storm was nearly stationary.

HAZARD...Wind gusts of 45 to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
West Palm Beach, Jupiter, Palm Beach Gardens, Tequesta, North County
Airport, The Acreage, Caloosa, Philo Farms, Jupiter Farms, and
Limestone Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

&&

LAT...LON 2695 8010 2695 8011 2694 8012 2694 8010
      2674 8015 2675 8037 2696 8036 2696 8010
TIME...MOT...LOC 2045Z 240DEG 4KT 2691 8024

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

GR

Special Weather Statement
National Weather Service Miami FL
446 PM EDT Thu Aug 20 2026

FLZ067-071-072-202115-
Inland Broward County FL-Metro Broward County FL-
Inland Palm Beach County FL-
446 PM EDT Thu Aug 20 2026

...A strong thunderstorm will impact portions of central Broward and
southern Palm Beach Counties through 515 PM EDT...

At 446 PM EDT, National Weather Service meteorologists were tracking
a strong thunderstorm near Mile Marker 30 On Alligator Alley, or 17
miles west of Sunrise. This storm was nearly stationary.

HAZARD...Wind gusts of 45 to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Weston, Mile Marker 30 On Alligator Alley, East Toll Gate On
Alligator Alley, Intersection I-75 And U.S. 27, and Intersection
Alligator Alley And Miami Canal.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

&&

LAT...LON 2607 8062 2624 8070 2635 8051 2615 8041
TIME...MOT...LOC 2046Z 240DEG 4KT 2619 8058

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

GR

Special Weather Statement
National Weather Service Miami FL
448 PM EDT Thu Aug 20 2026

FLZ066-070-202115-
Hendry FL-Inland Collier County FL-
448 PM EDT Thu Aug 20 2026

...A strong thunderstorm will impact portions of north central
Collier and northwestern Hendry Counties through 515 PM EDT...

At 448 PM EDT, National Weather Service meteorologists were tracking
a strong thunderstorm near Felda, or 8 miles northwest of Immokalee.
This storm was nearly stationary.

HAZARD...Wind gusts of 45 to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Labelle, Ave Maria, Immokalee, Felda, Orangetree, Big Corkscrew
Island, Port La Belle, Keri, Lake Trafford, and Bunker Hill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

&&

LAT...LON 2642 8158 2642 8156 2673 8157 2675 8141
      2655 8138 2630 8138 2628 8159
TIME...MOT...LOC 2048Z 235DEG 2KT 2650 8153

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

GR