Areal Flood Advisory 21, NWS Miami, FL

Area Forecast Discussion
National Weather Service Miami FL
421 AM EDT Wed Jun 7 2017

.DISCUSSION...

...Flood Watch Remains In Effect For Most of South Florida...

TODAY THROUGH THURSDAY: A wet and stormy pattern continues across
South Florida over the next few days, with significant flooding
remaining the primary concern.

The southern extension of the larger east coast mid-upper level
trough will continue to move slowly across the northeastern Gulf
today, getting absorbed into the larger system as it crosses North
Florida on Thursday. Weak surface low following this feature
evolves into a large, broad surface trough as it crosses the FL
peninsula. The trough will eventually slide into the Lake Okeechobee
region as a weak front late Thursday.

Several weaker shortwaves will continue to rotate around the base of
the trough and across the peninsula, lifting out waves of deep
moisture from the NW Caribbean. A lingering surface boundary will
continue to provide the focus for this moisture across South
Florida.

Today looks to be the wetter of the two days, with a sub-tropical
jet over the state continuing to contribute to 30-35kt winds at
850mb, enhancing the moisture uplift over the boundary. Gusty storms
and isolated tornadoes/waterspouts will also remain a threat in
addition to flooding rainfall. Cloud cover and ongoing stratiform
rain will continue to limit any widespread severe threat, but any
breaks in the clouds/sunshine may enhance it. The threat for heavy
rain will be maximized wherever the low level boundary resides,
which right now remains along a Mainland Monroe to Broward axis.

By Thursday, band of subsidence around the trough evident on water
vapor satellite will move into the region. This will bring in some
drier air, but not necessarily dry air, over the the Gulf coast and
western interior.

FRIDAY INTO EARLY NEXT WEEK: Frontal boundary, and some drier air,
is able to briefly reach as far south as Lake Okeechobee by midday
Friday. Boundary washes out over the weekend, with tropical moisture
re-establishing across the region for the weekend.

While rain chances will remain elevated, the pattern looks to shift
to more typical summertime diurnal pattern into early next week as
high pressure rebuilds to the north and easterly flow increases.

&&

.MARINE...Weak surface low slowly makes its way across the Gulf and
across Central/N Florida through Thursday, bringing a weak front
into the Lake Okeechobee region by Friday. The result will be
continuing gusty south-southwest winds through Thursday, with speeds
generally 15-20kts. The advisory for the Gulf has been extended
through this afternoon based on current observations, with
sustained winds closer to 20 knots north of the oscillating
boundary. Elsewhere, sustained 20kts will be possible at times,
however at this time it looks like a cautionary statement will be
more representative. Winds diminish on Friday to 10-15kts with
the front. The front is expected to wash out by Saturday, with
high pressure building to the north for the weekend with
prevailing flow becoming southeasterly into early next week.

Widespread showers with embedded thunderstorms will remain in the
forecast through much of the period. Locally higher winds and seas
can be expected near any convection.

&&

.AVIATION...Light and variable winds will be interrupted at
times by passing showers or thunderstorms. Light to moderate rain
will continue at all terminals through the TAF period but VFR will
prevail, however, brief MVFR conditions are possible with the
heaviest downpours. Similar trend continues into the late morning
and afternoon hours, but with more thunderstorm activity and
becoming SW and gusty.

&&

.HYDROLOGY...Two days rainfall totals across a wide swath of the
region are above 5 inches, with a higher corridor of 10-15 inches
stretching from Marco Island into the west Broward and SW Palm Beach
metro areas. While rain rates have diminished currently, the ground
remains saturated across much of the region. Most low-lying areas
and swales full in areas that have received the heaviest rainfall
with reports of street flooding and road closures ongoing.

A Flood Watch remains in effect through this evening for all of
South Florida except Glades and Mainland Monroe Counties where
rainfall amounts have not been as high. Rainfall amounts over Miami-
Dade County are also a little lower, but given antecedent rains from
the past weekend with the urbanization, the potential for flooding
remains high in this area as well. Any additional rainfall in the
next few days will lead to flooding, potentially significant.
An extension of the watch may be necessary later today if the
expected drier air slot does not reach the region.

&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  85  75  87  76 /  80  60  70  40
Fort Lauderdale  85  76  88  77 /  80  70  70  50
Miami            87  76  89  77 /  80  80  70  50
Naples           84  77  86  77 /  80  60  60  30

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Flood Watch through this evening for FLZ066>074-168-172>174.
AM...None.
GM...Small Craft Advisory until 5 PM EDT this afternoon for
     GMZ656-676.

&&

DISCUSSION...88/ALM
MARINE...88/ALM
AVIATION...17/AR
HYDROLOGY...88/ALM

Hazardous Weather Outlook for South Florida
National Weather Service Miami FL
413 AM EDT Wed Jun 7 2017

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
072015-
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-
413 AM EDT Wed Jun 7 2017

...THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL TODAY AND TONIGHT...
...ISOLATED TORNADOES AND WATERSPOUTS POSSIBLE THROUGH TONIGHT...

This hazardous weather outlook is for South Florida.

.DAY ONE...TODAY AND TONIGHT

Thunderstorms: another round of widespread showers with embedded
thunderstorms is expected today across South Florida. Main threats
will be locally heavy rainfall and lightning. The strongest storms
will also be capable of producing periods of gusty winds. Isolated
tornadoes and waterspouts cannot be ruled out.

Flooding: Heavy rainfall may again lead to some flooding conditions
across most of South Florida, especially over areas that are already
saturated. A Flood Watch is in effect for all areas except Mainland
Monroe and Glades Counties.

Tornadoes: Conditions are favorable for isolated tornadoes and
waterspouts across all of South Florida and the adjacent waters today.

Wind: The strongest storms today will be capable of producing wind
gusts of 60 mph or higher.

Rip Currents: There is a moderate risk of rip currents for the Gulf
Coast Beaches of South Florida.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

Thunderstorms will continue to be possible each day with periods of
heavy rainfall leading to areas of urban flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter may report any flooding, strong wind gusts in excess of 45
mph, waterspouts or tornadoes to the National Weather Service in
Miami.

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