Special Marine Warning 76, NWS Miami, FL

Area Forecast Discussion
National Weather Service Miami FL
744 AM EDT Tue Apr 20 2021

.AVIATION(12Z TAFS)...

Bouts of MVFR/IFR are possible once again across South Florida
especially later this afternoon. Patchy and light stratiform rain
will prevail across South Florida this morning before shower and
thunderstorm activity begins to increase during the mid-day to
early afternoon hours. Light southwesterly flow this morning will
become breezy and gusty at times this afternoon, then back to a
light flow after sunset.

&&

.PREV DISCUSSION... (Issued 339 AM EDT Tue Apr 20 2021)

..WIDESPREAD RAIN AND SCATTERED THUNDERSTORMS CONTINUE TODAY...

DISCUSSION...

SHORT TERM (Through Wednesday):

A frontal boundary remains quasi-stationary around the Lake region,
and keeping SoFlo under SW flow, which in turn keeps advecting deep
and warm air from the Caribbean. Model solutions also depict another
mid-level shortwave feature traveling along the boundary, which will
also contribute to supporting flares of deep convection through the
rest of today.

Already radar has shown a couple of instances where training of
cells has taken place, with 1 hour unbiased accumulations indicating
2-3 inches in places near Liberty city and Miami Shores during the
overnight hours. It is still a long way before this event is
over, so a watchful eye will be kept for such instances where
training of cells and colliding boundaries may operate in order to
keep persistent rainfall over the same location.

As advertised, the moisture profile continues to increase, not only
over the lake region but all across SoFlo, with PWAT values in the
1.5 to 2 inches range today. And along with CAPE around 2K, 500 mb
temps around -10C, and sufficient bulk shear values, expect
additional rounds of showers through this evening with localized
flooding possible. This afternoon looks like the best time for
daytime heating to further enhance potential for strong to severe
cells, with concerns being damaging winds, hail, excessive rainfall,
and even an isolated tornado can't be ruled out. That said, daytime
heating should take a modest hit from the persisting cloud cover and
shower activity, but still be able to push highs into the mid to
upper 80s over much of the area.

Similar general scenario on Wednesday, with models hinting at the
first sings of the front finally pushing a little further south
during the late afternoon and into the early evening hours.

LONG TERM (Wednesday Night through Monday):

Long range models finally show an initial push of the front over
central Florida, which seems to moves across SoFlo on Thursday, and
clear the state by the evening hours. Guidance then shows good
consensus in bringing drier air behind the FROPA, with a break form
the wet pattern finally taking place.

By Friday, models show another trough deepening over the central
CONUS, which drags another frontal boundary into the northern
Gulf waters and towards the Florida peninsula during the upcoming
weekend. Uncertainty remains regarding the final solution of this
scenario, which will surely continue to evolve during the later
part of the long term.

Lingering cloud cover should keep high temperatures in the low-mid
80s on Thursday, then a warming trend returns to the area on Friday
with afternoon highs back into the upper 80s to near 90 for the
weekend.

MARINE...

A cold front moving located across central Florida is bringing
widespread showers and scattered thunderstorms through the middle
of the week. Winds may reach cautionary levels at times over the
Atlantic waters this afternoon. Strong to severe thunderstorms may
develop over the coastal waters during the next couple of days,
bringing brief periods of gusty winds and rough seas.

BEACHES...A Moderate Risk of Rip Currents continues today for all
the Palm Beaches.

&&

.PRELIMINARY POINT TEMPS/POPS...
Miami            74  85  70  84 /  60  70  30  40
West Kendall     73  86  68  86 /  60  60  30  40
Opa-Locka        74  85  68  84 /  60  70  30  40
Homestead        72  85  68  84 /  50  60  30  40
Fort Lauderdale  74  84  70  83 /  60  80  30  40
N Ft Lauderdale  73  84  69  81 /  60  80  30  40
Pembroke Pines   73  85  68  84 /  60  80  30  40
West Palm Beach  70  83  67  81 /  70  70  20  30
Boca Raton       72  83  68  83 /  60  80  30  30
Naples           72  81  66  85 /  70  70  10  20

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
GM...None.
&&

Update/Aviation...Hadi
Today through Wednesday and Marine...AR
Wednesday Night through Monday...AR

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Hazardous Weather Outlook for South Florida
National Weather Service Miami FL
419 AM EDT Tue Apr 20 2021

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
202030-
Lake Okeechobee-Biscayne Bay-
Coastal waters from Jupiter Inlet to Deerfield Beach FL out 20 NM-
Coastal waters from Deerfield Beach to Ocean Reef FL out 20 NM-
Waters from Jupiter Inlet to Deerfield Beach FL from 20 to 60 NM-
Waters from Deerfield Beach to Ocean Reef FL from 20 to 60 NM
excluding the territorial waters of Bahamas-Glades-Hendry-
Inland Palm Beach-Metro Palm Beach-Coastal Collier-Inland Collier-
Inland Broward-Metro Broward-Inland Miami-Dade-Metro Miami-Dade-
Mainland Monroe-Coastal Palm Beach-Coastal Broward-Coastal Miami-
Dade-Far South Miami-Dade-
Coastal waters from Chokoloskee to Bonita Beach FL out 20 NM-
Coastal waters from East Cape Sable to Chokoloskee FL out 20 NM-
Waters from Chokoloskee to Bonita Beach FL from 20 to 60 NM-
419 AM EDT Tue Apr 20 2021

...Showers and Thunderstorms Continue Today...
...Moderate Risk of Rip Currents for the Palm Beaches...
...Localized Flooding Possible Today...

This hazardous weather outlook is for South Florida.

.DAY ONE...TODAY AND TONIGHT

Thunderstorms: scattered thunderstorms continue across the area, with
primary hazards being will be lightning strikes, locally heavy
rainfall, and gusty winds.

Flooding: periods of heavy rain can result in localized flooding,
especially over urban areas with poor drainage. Multiple storms
affecting the same area will lead to accumulation of water on roads,
especially intersections prone to flooding.

Hail: some thunderstorms may produce hail today.

Wind: the strongest thunderstorms may produce brief periods of
gusty winds that could reach 50 mph or higher. Severe storms may
produce damaging winds this afternoon.

Waterspouts: a waterspout or two may be possible in the stronger
thunderstorm activity.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

Chances of strong to severe thunderstorms on Wednesday as a frontal
boundary meanders around and north of South Florida through Thursday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated, but individual spotters are
encouraged to report any significant weather events to the National
Weather Service Office in Miami.

For more information...visit the National Weather Service in
Miami website at www.weather.gov/miami.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
304 AM EDT TUE APR 20 2021

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

0245 AM     MARINE TSTM WIND 1 S NORTH MIAMI BEACH   25.91N 80.16W
04/20/2021  M42 MPH          MIAMI-DADE         FL   MESONET

            A MARINE THUNDERSTORM WIND GUST OF 42 MPH /
            36 KNOTS WAS RECORDED BY MESONET STATION
            XNMI NORTH MIAMI.

&&

WEINMAN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
325 AM EDT TUE APR 20 2021

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

0304 AM     MARINE TSTM WIND 2 NE DANIA BEACH        26.09N 80.12W
04/20/2021  M50 MPH          BROWARD            FL   MESONET

            A MARINE THUNDERSTORM WIND GUST OF 50 MPH /
            43 KNOTS WAS RECORDED BY MESONET STATION
            XPEG PORT EVERGLADES.

&&

WEINMAN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
331 AM EDT TUE APR 20 2021

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

0303 AM     MARINE TSTM WIND 1 E DANIA BEACH         26.06N 80.13W
04/20/2021  M39 MPH          BROWARD            FL   MESONET

            A MARINE THUNDERSTORM WIND GUST OF 39 MPH /
            34 KNOTS WAS RECORDED BY MESONET STATION
            XPES PORT EVERGLADES SOUTH.

&&

WEINMAN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
354 AM EDT TUE APR 20 2021

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

0331 AM     TSTM WND GST     1 NW DANIA BEACH        26.07N 80.15W
04/20/2021  M41 MPH          BROWARD            FL   ASOS

            A THUNDERSTORM WIND GUST OF 41 MPH WAS
            RECORDED BY ASOS STATION KFLL FORT
            LAUDERDALE/HOLLYWOOD INTL AIRPORT.

&&

WEINMAN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
355 AM EDT TUE APR 20 2021

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

0327 AM     TSTM WND GST     NORTH PERRY AIRPORT     26.00N 80.23W
04/20/2021  M41 MPH          BROWARD            FL   ASOS

            A THUNDERSTORM WIND GUST OF 41 MPH WAS
            RECORDED BY ASOS STATION KHWO PEMBROKE
            PINES.

&&

WEINMAN

Special Weather Statement
National Weather Service Miami FL
542 AM EDT Tue Apr 20 2021

FLZ067-068-168-201030-
Coastal Palm Beach County FL-Inland Palm Beach County FL-
Metro Palm Beach County FL-
542 AM EDT Tue Apr 20 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN PALM BEACH COUNTY
UNTIL 630 AM EDT...

* At 542 AM EDT, National Weather Service meteorologists were
  tracking a strong thunderstorm 10 miles east of Canal Point, moving
  northeast at 30 mph.

* Winds in excess of 45 mph possible with this storm.

* Locations impacted include...
  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.

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm. If
you can hear thunder, you are close enough to be struck! Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 2692 8003 2671 8048 2687 8058 2696 8043
      2696 8014 2697 8014 2697 8003
TIME...MOT...LOC 0942Z 244DEG 24KT 2683 8046

Hadi/CWC