Florida Weather

[RL3AO]

There are gonna be three things to watch with this potential TC and none of them are the wind.

- Heavy rainfall/local flooding
- Tornadoes south of the low
- Localized 3' + storm surge around Tampa and northward

[northjaxpro]

There are gonna be three things to watch with this potential TC and none of them are the wind.

- Heavy rainfall/local flooding
- Tornadoes south of the low
- Localized 3' + storm surge around Tampa and northward

Yes pretty much sums things up, although there could be winds at or near tropical storm force near the coast, and some wind gusts in some of the heavy rain/storm bands rotating through the peninsula. I would also add that tornadoes also are possible to the east of the Low Pressure area as well as those bands rotate counterclockwise through the peninsula.

[northjaxpro]

This afternoon's NWS Melbourne AFD excerpt pertaining to the tropical cyclone for Monday-Tuesday

Mon-Tue...Deep tropical moisture will overspread the entire region
by early Monday associated with the approach of a developing low
pressure emerging over the SE Gulf. A Flood Watch will likely be
in effect. Models in fair agreement with organizing/moving the
system toward the W FL Peninsula Mon night into Tue. Associated
convection and wind fields should dominate on the east side of the
low center nearing 34 knot thresholds. Although uncertainty exists
in the unfolding of the exact forecast/track and its potential
tropical characteristics, confidence is increasing for a heavy
rain event along with embedded squalls overspreading all of east
central florida early Monday and into Monday night. The low is
forecast to exit the NE FL coast early Tue with active weather /
storms early Tue over portions of the area. Shear and helicity
should be more than sufficient for tornado development...
especially Monday and Monday night. Event rain totals could reach
3 to 6 inches with locally higher amounts


This afternoon's NWS Ruskin (Tampa Bay) AFD excerpt

.LONG TERM (Sunday Night-Saturday)...
Some uncertainty still exists regarding the first couple of days
of the forecast period with regards to a tropical disturbance in
the Western Caribbean approaching and affecting Florida. The
GFS/ECMWF continue to be fairly similar with the location and
timing of a low (most likely becoming tropical in nature)
forecast to develop near the Yucatan on Sunday with this low then
lifting north-northeast through the eastern Gulf of Mexico during
Monday and Monday night. Models still differ some with the overall
development and intensity of this system...but despite this a
blend of these models will still be used during this time frame.

In using a blend of the models the heaviest rains and strongest
winds associated with this developing tropical system would
affect the region during Monday and Monday night, with some
improving conditions expected by late on Tuesday as the low lifts
out to the northeast. Since we are talking about a system that has
yet to develop, a lot could still change between now and then, so
stay tuned to the latest forecasts and updates. In any event, the
main impact from this system at the current time appears to
flooding rains with widespread amounts of 4 to 6 inches a good
bet, with higher amounts possible where the training of cells
occur.

In addition the possibility of isolated tornadoes and marine
waterspouts will be possible as wind shear through the
atmospheric column increases across the region as this system
approaches and moves across the region, especially during Monday
afternoon and night. Based on the current model track of this
system somewhere toward the Big Bend area of Florida, coastal
flooding may also become an issue as well, especially during times
of high tides during Monday and Monday night and continuing into
early Tuesday.

[northjaxpro]

This afternoon's NWS Miami AFD excerpts

Regardless of the classification of this event, the major impacts
to southern Florida are expected to be heavy rain/flooding,
strong winds over the Gulf waters, and the potential for strong
thunderstorms that could produce tornadoes. Anyone with interests
in southern Florida should monitor the progress of this system
over the next several days at the event unfolds. Sunday will be an
important day to follow the forecast evolution and make sure you
have your ready kit as conditions will begin to deteriorate on
Monday.

Looking at the heavy rain/flood threat, it appears that the deep
tropical moisture associated with this system will create the
potential for accumulations of rainfall of 3 to 4 inches for the
event. Localized amounts exceeding 4 inches are possible as
well, mainly along the Collier coast.

Another potential threat is tornadic storms. The latest model
guidance is not painting a pretty picture for much of the southern
half of the peninsula of Florida as lower level shear values will
be increasing on Sunday night into Monday across the region. This
could pose an emerging nocturnal tornado threat late Sunday night
into Monday morning, currently with a focus over Southwest
Florida, that grows on Monday to include other portions of
southern and central Florida by Monday afternoon and evening. The
12z GFS offers 0-1 km helicity values exceeding 200 m2/s2 over
southwest Florida on Monday with the 12z ECMWF not much behind
that around 100 m2/s2. There is still great uncertainty with this
system, but the tornadic threat may indeed present itself even if
the storm center tracks further away from the region.

While on the topic of the potential track of the low, the latest
runs have trended further north. This has decreased the potential
for strong sustained winds from affecting the landmass of southern
Florida, but the marine waters could still see some strong
sustained winds. There is plenty of uncertainty with track and
timing with this potential system, but the consensus is that the
system will push into the Gulf on Monday. As the center nears the
Florida Big Bend or Nature Coast regions late Monday into early
Tuesday, the peninsula will sit on the wet eastern side of the
system. The frontal system will approach and help push the system
northeastward into the Atlantic on Tuesday.

[northjaxpro]

This afternoon's NWS Jacksonville AFD excerpts. Very good analysis! 3-6 inches is now forecast for the Northeast Florida area for the period ending Tuesday evening.

Mid Term...Monday through Tuesday...

Model guidance remains in fairly good agreement depicting a sheared,
weak tropical cyclone moving N-NE over the eastern Gulf of Mexico on
Monday. Historically, sheared tropical cyclones over the eastern
Gulf feature a large convective band over or east of the cyclone`s
center, with little activity on the west side of the cyclone`s
circulation. A large convective band will likely move eastward over
the FL peninsula as the day progresses on Monday, with the less
certain meteorological feature being a frontal boundary that will be
pushing southward through central GA as a trough aloft digs
southeastward from the Great Lakes. Global models agree that the
center of this potential tropical cyclone will be located about 275
miles to the west of Naples at 12Z Monday. Outer rain bands will
begin to move onshore along the Florida west coast and Big Bend
regions early on Monday morning. Additional shortwave energy
embedded in deep southwesterly flow will also be streaming over our
region early on Monday, with some extra forcing also from the
approaching front possibly sparking scattered activity around
sunrise as PWATs spike to well above 2 inches. The anticipated
convective band will then impact almost all of our region by the
late morning and afternoon hours on Monday, which will likely
produce widespread rainfall totals near 1 inch by Monday evening,
with higher totals nearing 1.5 inches for north central FL. Heavy
rainfall rates on Monday afternoon may necessitate Flood Watches in
future forecasts for portions of our area. Categorical POPS were
used for all locations in the forecast grids for Monday afternoon.
Clouds and rainfall will keep highs generally in the mid 80s area-
wide.

Troughing aloft digging into the Tennessee Valley will push the
aforementioned frontal boundary into interior southeast GA on Monday
night and will also provide an impetus to accelerate the potential
cyclone northeastward towards the FL Big Bend coast overnight. The
12Z operational ECMWF and NAM models are positioned slightly west of
the 12Z operational GFS with regards to landfall late Monday night
and early Tuesday morning. All models continue to show a highly
sheared cyclone, with differences in how the frontal boundary over
inland southeast GA will factor into potential rainfall enhancement
or possibly a mechanism for brief tornado spin-ups. Southeasterly
winds will increase over coastal locations and north central FL as
our local pressure gradient tightens with the approach of the
cyclone. As the primary convective band departs our region during
the evening hours, there is more uncertainty in how much convection
will redevelop near and east of the cyclone`s center, with a
potential dry slot rotating into our region overnight while
isentropic lift possibly keeps convection firing over inland
southeast GA close to the stalled front. The ECMWF depicts a very
dry air mass filtering into the southeastern states in the wake of
the cyclone, which may shut off rainfall over inland southeast GA
and the western Suwannee Valley towards sunrise on Tuesday. We will
thus taper POPS after midnight from NW to SE. Lows will remain in
the low/mid 70s region-wide.

The potential tropical cyclone will be accelerating northeastward
along or just north of I-10 during the early morning hours on
Tuesday, emerging into the Atlantic waters adjacent to southeast GA
by the late morning hours. The 12Z operational NAM remains an
outlier, depicting an extratropical transition that stretches the
low out along the surface boundary positioned near the FL/GA border
on Tuesday morning. We kept likely POPs in the grids from
Gainesville/Ocala/Macclenny and points eastward during the early
morning hours, with scattered coverage elsewhere and then gradually
decreasing chances from northwest to southeast as the day
progresses. Rainfall amounts from Sunday through Tuesday will likely
fall in the 3"-6" range. These amounts would cause primarily urban
flooding concerns and minor flooding possible along faster rising
tributaries such as Black Creek in Clay County. Decreasing cloud
cover and offshore winds on Tuesday afternoon may allow highs to
approach 90 degrees area-wide.

[northjaxpro]

This afternoon's NWS Tallahassee AFD excerpts

Meanwhile, a tropical disturbance currently in the northwestern
Caribbean Sea is expected to develop as it drifts northward over the
Yucatan Peninsula. The NHC is showing a 70% chance of this system
developing within the next 48 hours, so there is the possibility of
a tropical storm watch being issued sometime tomorrow. Current model
consensus and NHC forecast show this system reaching tropical storm
strength and coming ashore near the Suwannee River Monday night.
Given how quickly this system will develop and that it will be
fighting some westerly shear from the stalled front, this system is
expected to be asymmetric with the strongest winds and heaviest
rain on the east side of the storm.

Locally what this will mean for us is showers and thunderstorms
Sunday through Monday night, with rainfall Sunday and Sunday
night driven by the frontal system and rainfall Monday and Monday
night driven more by the tropical system. Widespread totals of
2-3" will be possible with areas of 3-5" in the southeastern Big
Bend.

[northjaxpro]

Meanwhile, NWS Key West WFO mets are calling for generally 1-3 inches down there.

Monday and Tuesday...The low will move fairly rapidly through the
east central Gulf on its way towards north Florida or the northern
portion of the peninsula. Depending on which GSM depiction will be
closer to reality depends on what winds will be realized. Regardless,
squally weather and strong thunderstorms are likely from Sunday night
through Tuesday morning. By Tuesday afternoon winds should decrease
fairly rapidly as the system moves off the peninsula into the
Atlantic waters. Rainfall totals of 1-3 inches are possible through
Tuesday, with isolated higher amounts

[psyclone]

it reached 95 today at Tampa international resulting in hideous heat index numbers. Bring on the storm...whatever it is. Let 'er dump!

[northjaxpro]

Checked the models and I really am growing increasingly concerned about tornadoes for the peninsula tomorrow into Monday evening. Helicity indicators and shear profiles look rather decent for the formation of tornadoes as the tropical cyclone approaches the peninsula. Another concern is daytime heating. There is a possibility that before the onset of the rainbands rotating through the peninsula, enough daytme heating could occur to further aggitate the atmosphere with even more energy and instability favorable to form severe weather or tornadic cells.

Tomorrow could be one of those days in which we will see many severe weather or tornado reports, as you would expect with landfalling tropical cyclones. This thread will be very helpful and useful for indicating and posting photos throughout the peninsula concerning severe weather and potential tornadoes.

[MetroMike]

NHC will initiate advisories for a TD at 11am with a TS Warning for parts of the Florida West Coast.

[AdamFirst]

After TD 3/Colin moves out from the peninsula, the trough that punts the system out is expected to stall over central or southern Florida. The southern half of the peninsula may end up getting more rain from the trough stall than TD 3/Colin.

Heavy Rain/Flooding: With South Florida expected to be on the wet
eastern side of the system, there will be the potential for rainfall
accumulations of 2 to 5 inches through the week. Localized amounts
exceeding 5-6 inches are possible, mainly along the Collier coast.

It is important to remember that the heavy rain threat for South
Florida will continue through the week. We may see some of our
heaviest rainfall later in the week.

[northjaxpro]

Yes indeed, A very wet week is in store for South Florida as the frontal system will stall out it appears near or just south of the Interstate 4 corridor. All of that deep tropical moisture will converge on those areas along and south of the boundary.

First outer rainband affecting the peninsula nowcurrently clipping the Naples area. That band is mostly staying off shore as it rotates northwest in the Gulf waters on the outer periphery of TD 3. Also, heavy showers and thunderstorms are now developing up in the Big Bend region and panhandle associated with the frontal boundary pushing down toward the peninsula.

[northjaxpro]

NWS WFO Ruskin radar shows the long ,first pronounced rainband from TD 3 rotating along the coast from Everglades City all the way up through Tampa Bay to Pasco County. I am a bit surprised the Ruskin mets have not issued a special statement on the cell in Tampa Bay currently. That cell looks strong.

[northjaxpro]

Yes, they put out a special marine warning:

SPECIAL MARINE WARNING
GMZ830-051800-
/O.NEW.KTBW.MA.W.0073.160605T1709Z-160605T1800Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA / RUSKIN FL
109 PM EDT SUN JUN 5 2016

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

* SPECIAL MARINE WARNING FOR...
TAMPA BAY WATERS...

* UNTIL 200 PM EDT

* AT 108 PM EDT...A STRONG THUNDERSTORM WAS LOCATED NEAR TAMPA BAY...
MOVING NORTH AT 20 KNOTS.

HAZARD...WIND GUSTS 34 KNOTS OR GREATER.

SOURCE...RADAR INDICATED.

IMPACT...SMALL CRAFT COULD BE DAMAGED IN BRIEFLY HIGHER WINDS AND
SUDDENLY HIGHER WAVES.

* LOCATIONS IMPACTED INCLUDE...
COURTNEY CAMPBELL CAUSEWAY...HOWARD FRANKLAND BRIDGE...HILLSBOROUGH
BAY...GANDY BRIDGE...OLD TAMPA BAY...COCKROACH BAY AND TAMPA BAY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO SAFE HARBOR UNTIL HAZARDOUS WEATHER PASSES

[northjaxpro]

Web Cam showing heavy rainband currently over Tampa Bay.

[northjaxpro]

As anticipated, the first of the Flood Watches has just been issued by the NWS Melbourne WFO for their entire forecast zone of East-Central Florida. I am pretty sure the other NWS WFOs across the state will follow suit in their AFDs this afternoon.


FLOOD WATCH
NATIONAL WEATHER SERVICE MELBOURNE FL
256 PM EDT SUN JUN 5 2016

...HEAVY RAIN IN FORECAST ON MONDAY...

FLZ041-044>047-053-054-058-059-064-141-144-147-062000-
/O.NEW.KMLB.FA.A.0003.160606T0800Z-160607T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
INLAND VOLUSIA COUNTY-NORTHERN LAKE COUNTY-ORANGE-SEMINOLE-
SOUTHERN BREVARD COUNTY-OSCEOLA-INDIAN RIVER-OKEECHOBEE-ST. LUCIE-
MARTIN-COASTAL VOLUSIA COUNTY-SOUTHERN LAKE COUNTY-
NORTHERN BREVARD COUNTY-
INCLUDING THE CITIES OF...DEBARY...DELAND...DELTONA...EUSTIS...
MOUNT DORA...LEESBURG...TAVARES...APOPKA...MAITLAND...ORLANDO...
WINTER PARK...UNION PARK...ALTAMONTE SPRINGS...CASSELBERRY...
OVIEDO...SANFORD...WINTER SPRINGS....MELBOURNE...PALM BAY...
ROCKLEDGE...CELEBRATION...KISSIMMEE...SAINT CLOUD...SEBASTIAN...
VERO BEACH...BASINGER...FORT DRUM...OKEECHOBEE...
PORT SAINT LUCIE...FORT PIERCE...HOBE SOUND...JENSEN BEACH...
PORT SALERNO...STUART...DAYTONA BEACH...NEW SMYRNA BEACH...
ORMOND BEACH...CLERMONT...MASCOTTE...GROVELAND...COCOA...
TITUSVILLE
256 PM EDT SUN JUN 5 2016

...FLOOD WATCH IN EFFECT EARLY MONDAY THROUGH MONDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* FLOOD WATCH FOR A PORTION OF EAST CENTRAL FLORIDA...INCLUDING
THE FOLLOWING AREAS...COASTAL VOLUSIA COUNTY...INDIAN RIVER...
INLAND VOLUSIA COUNTY...MARTIN...NORTHERN BREVARD COUNTY...
NORTHERN LAKE COUNTY...OKEECHOBEE...ORANGE...OSCEOLA...
SEMINOLE...SOUTHERN BREVARD COUNTY...SOUTHERN LAKE COUNTY AND
ST. LUCIE.

* FROM LATE TONIGHT THROUGH MONDAY EVENING

* SHOWERS AND SQUALLS CONTAINING OCCASIONAL LIGHTNING STORMS WILL
MOVE NORTHWARD ACROSS EAST CENTRAL FLORIDA ALL DAY MONDAY.
PERIODS OF HEAVY RAIN ARE EXPECTED WITH EVENT RAIN TOTALS OF 3
TO 5 INCHES POSSIBLE OVER THE WATCH AREA. LOCALLY HIGHER AMOUNTS
WILL BE POSSIBLE.

* STANDING WATER WILL OCCUR IN TRADITIONALLY FLOOD PRONE LOCATIONS
...INCLUDING STREETS AND LOW ELEVATION AREAS. RAINFALL WILL TEND
TO ACCUMULATE WHERE HEAVY RAINS OCCURRED DURING THE MONTH OF
MAY AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLOOD WATCH MEANS THERE IS A POTENTIAL FOR FLOODING BASED ON
CURRENT FORECASTS.

YOU SHOULD MONITOR LATER FORECASTS AND BE ALERT FOR POSSIBLE
FLOOD WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE
PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP.

&&

[northjaxpro]

NWS Miami has issued FLOOD Watch for Southwest Florida for Collier, Henry and Glades counties. They have yet to post FLOOD Watch for Southeast Florida counties just yet. May be required for Dade, Broward and Palm Beach counties late tonight or early Monday. They are monitoring to see how the bands will set up across the region overnight. The mets there mentioned in the AFD that they are monitoring potential for "training" bands later tonight into Monday, which could prompt Flood Watch later.

[northjaxpro]

NWS JAX just released their AFD. Expecting the greatest impact from TD 3 /Colin to occur tomorrow night into Tuesday morning in the Jacksonville area. Possibly may see gusts up to 50 mph during that period, which could prompt bridge closings here during that period. This afternoon AFD excerpt:


Mon through Tue...

Bands of rainfall from approaching TD 3 will
begin to impact the Suwannee River Valley by midday Mon with
widespread rainfall overspreading the forecast area Monday
afternoon and pushing ENE across the remainder of the area through
Monday night. Rainfall amounts of 2-4 inches are likely with
isolated higher amounts of 6-8 inches possible. Still uncertain as
to where highest rainfall bands will impact as recent model
guidance shifted higher rainfall amounts farther west and even
more northward. Thus will refrain from a Flood Watch until
guidance trends in QPF become better resolved and consistent. In
addition to heavy rainfall there will be a severe storm threat
with cells capable of producing strong wind gusts and isolated
tornadoes Monday afternoon through Monday night. Again...models
are not consistent in where strongest swath of 0-1km helicity
traverses but between both the NAM12 and GFS20 there is a
reasonable threat of rotating cells as shear increases over the
area on the east side of the approaching depression. As the storm
moves quickly across the local area Mon night inland areas will
likely experience a period of sustained winds between 20-35 mph
with gusts of 40-50 mph possible in stronger squalls. Tropical
storm force gusts will be possible late Monday night/early Tuesday
morning along the Atlantic coast...then winds speeds quickly
decrease Tuesday morning as the low pressure quickly ejects NE of
the local waters trailing a wake trough across the area with a
drier northerly flow across SE Ga Tuesday afternoon and lingering
scattered convection across NE Florida. Temperatures will be
greatly moderated by cloud cover and range only in the lower 80s
Tue...lows in the mid/upper 70s Tue night...then rebound into the
upper 80s/near 90 inland Tue afternoon.

[northjaxpro]

NHC has just posted at 5:00 a Tropical Storm Watch for the Northeast Florida coast from Fernandina Beach south to Flagler Beach.

[northjaxpro]

Currently, a very intense rainband extends up the spine of the peninsula currently looking at radar above on this page. Some of these cells may be producing severe weather, really being aided by the 90 plus degree heat across the interior. The large rainband is moving north/northwest. This will move into North Florida later tonight.