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000
FXUS62 KTBW 241318
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
918 AM EDT TUE MAY 24 2016

.SYNOPSIS...
13Z water vapor and H4 RAP analysis continues to show the Florida
peninsula at the base of a longwave eastcoast upper trough that
this anchored by a large closed low spinning over the mid-atlantic
and northeastern states. Broad upper ridging is found upstream
from Mexico/western Gulf northward through the lower/middle MS
valley. The deep layer flow between these two features over our
region is from the west and northwest as sampled by the 12z KTBW
RAOB. Also within this NW flow we find a weak impulse/shortwave up
toward the Florida Panhandle. This feature will drop southeastward
through the day...helping to enhance the overall troughing over
the peninsula...and spreading a preceding swath of broad but weak
synoptic forcing/QVector convergence across the region this
afternoon/evening. This feature is a positive toward convection
later today. However...similar to Monday...this NW flow has also
delivered a deep layer of dry air above our heads. This dry air
is a general negative toward late day convection. 12Z sounding
shows large dewpoint depressions from just above the surface to
well above 400mb. The depth of this dry air is resulting in a very
low PW value for the end of May. The measured value this morning
was only 0.58". This is just about as dry as it gets around these
parts this time of year. If fact...it is the lowest value ever
recorded on the May 24th 12Z sounding...breaking the previous
daily min of 0.6". The 30 day moving average of the 10% percentile
PW value is a low 0.98"...so our current value shows we are sitting
under an exceptionally dry trop column for late May.

On the other hand...if one heads south...from Ruskin/Tampa Bay
area...there is a fairly tight gradient in the PW. The 12Z KMFL
RAOB sampled a PW of nearly 1.5". This gradient will define the
forecast story for today. From the Tampa Bay area
northward...despite the broad synoptic support/troughing aloft and
eventual low level seabreeze focus...it will be very difficult to
support much in the way of convection due to the overwhelming
degree of dry air for convective updrafts to overcome. The further
south one goes from the I-4 corridor...the more favorable the
atmosphere will become toward supporting or maintaining a few deep
convective updrafts.

At the surface...High pressure is centered off the SE conus coast
and ridges back to the west/SW over the northern half of the
Florida Peninsula and NE Gulf of Mexico. The gradient is fairly
light currently, but as the high better aligns itself through the
day...a more defined easterly flow in the lower levels is progged
by NWP guidance to develop. The easterly flow will be stronger
than previous days...and therefore the westcoast seabreeze will
have a more difficult time propagating inland. The better focus
staying closer to the coast should eventually align or propagate
any late day storms toward the I-75 corridor along the suncoast.
As mentioned above...despite the focus along the Nature
coast...little in the way of convection is expected...and barely
any of the hires convection allowing guidance are currently
showing storms north of Tampa Bay. An isolated pop up and short-
lived shower is not impossible, however coverage should be low
enough to exclude mention from the current forecast.

Forecast will show pops increasing from around 20% I-4 corridor to
the 30-50% range as one heads southward. Highest rain chances...as
mentioned...should align along the I-75 corridor from roughly
Sarasota southward to Fort Myers after 19-20Z. Despite still
having dry air aloft...the dry air will not be as pronounced as
further north...and combined with the other positive factors for
convection mentioned above...feel these rain coverages are
appropriate.

Temperatures today should max out within a degree or two either
side of 90 away from the beaches...and reach the middle 80s at the
immediate coast.

&&

.SHORT TERM (Tonight and Wednesday)...
Sct convective cells south of I-4 slowly dissipate between 01-03Z
with the loss of diurnal heating and sea-breeze focus. As during
any warm season day...residual outflow boundaries can focus
isolated cells for a bit longer...but these are tough to forecast
more than a couple hours in advance. With this in mind will end
pops after 03z...which is consistent with climatology. Low
temperatures by dawn will again be a bit below climo for late
May...with many inland area dropping down into the middle 60s.
Normally warmer locations with land breeze flow off the harbors
and Bays...such as southern Pinellas/coastal Charlotte/Lee
counties will likely stay in the lower 70s.

Wednesday currently looks as through it will be an inactive day
convectively for almost all zones. Shortwave impulse that will
help support some storms today will have sheared out and shifted
south of our region by tomorrow...with instead the enhanced
drying/subsidence in its wake arriving overhead. In
addition...defined easterly flow in the 1000-850mb range at times
exceeding 15kts should be enough to disrupt the organization of
the sea-breeze...or even keep it parked just offshore in some
spots. This lack of surface focus to initiate updrafts will
further decrease the potential for deep convection. Have excluded
mention of any rain chances for just about all zones. Only
exception is Lee county were a 20% chance for an isolated late day
shower has been painted. Lee county is in closest proximity to the
deeper moisture which will be down over far south Florida.
Sometimes a few storms are forced along these moisture gradients
leading to this small rain chance around Fort Myers.
However...anything in this area should be very isolated and short-
lived...and should have limited impact to any outdoor
plans/activities. Temperatures Wednesday remain seasonable with
upper 80s to lower 90s common.

&&

.MID/LONG TERM (Wednesday night through Monday)...
At the beginning of the medium range period, a large trough will
reside over the western half of the CONUS, bringing episodes of
thunderstorm activity from the Canadian border southward into the
Southern Plains. Further east, as a cutoff low lifts into the
northern Atlantic, broad upper ridging will become established from
the Gulf Coast states up into the Mid-Atlantic.

From Wednesday night through the end of the week, while weak upper
ridging looks to prevail, models continue to depict a weakness
developing across the western Atlantic near the Bahamas. Long range
solutions show this feature eventually evolving into a weak cutoff
low meandering northwestward through late week. With surface ridge
axis extending across northern Florida, a prolonged period of
easterly flow should promote increasing moisture from the Atlantic.
This increased moisture combined with weak lift in the presence of
the upper low should promote a daily increase in chances for
afternoon showers and thunderstorms across the peninsula.

From the weekend into early next week, the Atlantic upper low looks
to continue northwestward, opening up over the southeastern U.S. as
it is slowly absorbed into the larger upper trough moving eastward
early next week. Given the proximity of this feature and presence of
abundant moisture...expect scattered afternoon showers and storms
will remain possible through the weekend. Should the system track
well to the east of the Florida west coast, conditions may be drier
than currently forecast, as weak subsidence overspreads the
region.

Temperatures throughout the long range period look to remain in the
mid to upper 80s each afternoon, with lows in the upper 60s and
lower 70s most nights.

&&

.AVIATION...
24/12Z-25/12Z. VFR with FEW-SCT LCL BKN cumulus developing by
afternoon. Expect ISOLD late afternoon TSRA/CB with best odds for
LAL/PGD/FMY/RSW which have VCNTY TSRA. Light mostly easterly
winds...but shifting to onshore at coastal terminals in the
afternoon at 10kts or less. VCNTY TSRA ends by 03Z followed by
prevailing VFR and light east or variable winds at 6kts or less
through the overnight.

&&

.MARINE...
High pressure will ridge back over the northern Florida peninsula
and northeast Gulf of Mexico from the Atlantic through the
majority of the week. The position of the ridge will favor
stronger easterly surges each night and early morning. Overnight
winds are forecast to approach cautionary levels at
times...especially Wednesday night into early Thursday morning.

&&

.Preliminary Point Temps/PoPs...
TPA  88  71  89  69 /  10  10  10  10
FMY  89  71  88  69 /  40  30  20  20
GIF  89  69  87  67 /  10   0   0   0
SRQ  85  70  87  69 /  10  20  10  10
BKV  89  65  88  62 /  10   0  10   0
SPG  87  73  88  72 /  10  20  10  10

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.

&&

$$

SYNOPSIS/SHORT TERM/AVIATION/MARINE...Mroczka
MID TERM/LONG TERM...Austin





000
FXUS62 KTBW 240739
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
339 AM EDT TUE MAY 24 2016

.SYNOPSIS...
aloft - A ridge reached from the western Gulf of Mexico to the Great
Lakes while a low over the NJ/NY coastal waters troughed down to
the Bahamas. surface - high pressure sprawled from the south-
central Appalachians...a low was south of Long Island NY...and a
stalled frontal boundary stretched across far south FL.

&&

.SHORT TERM (Today through Wednesday)...
The upper ridge pivots from the Gulf to the eastern seaboard and
flattens as the NJ/NY upper low moves into the Canadian Maritimes
as a trough...leaving troughiness over the Bahamas. The
Appalachian high pressure tracks out over the western Atlantic
while elongating southwestward...across the Gulf. the frontal
boundary meanders over or south of South Florida.

The drier air of the past couple of days will give way to
increasing moisture working north this afternoon from the frontal
boundary to the south. Model pwat values increase into the 1 to
1.5 inch range from south to north...reaching as far as Tampa Bay
and locations east. This moisture along with afternoon sea breeze
convergence will support shower and thunderstorms...with a slight
chance around Tampa Bay and a chance south of there. Convection
is expected to wind down around sunset and drift toward the coast.
For Wed the upper ridge moving toward the eastern seaboard and the
trough east of FL will set up a more northerly flow aloft and push
the frontal boundary and it/s moisture to the south. Only a slight
chance of storms are expected late afternoon in the far south.
temperatures will run just under to near normal but become around
normal Wed.

&&

.MID/LONG TERM (Wednesday night through Monday)...
At the beginning of the medium range period, a large trough will
reside over the western half of the CONUS, bringing episodes of
thunderstorm activity from the Canadian border southward into the
Southern Plains. Further east, as a cutoff low lifts into the
northern Atlantic, broad upper ridging will become established from
the Gulf Coast states up into the Mid-Atlantic.

From Wednesday night through the end of the week, while weak upper
ridging looks to prevail, models continue to depict a weakness
developing across the western Atlantic near the Bahamas. Long range
solutions show this feature eventually evolving into a weak cutoff
low meandering northwestward through late week. With surface ridge
axis extending across northern Florida, a prolonged period of
easterly flow should promote increasing moisture from the Atlantic.
This increased moisture combined with weak lift in the presence of
the upper low should promote a daily increase in chances for
afternoon showers and thunderstorms across the peninsula.

From the weekend into early next week, the Atlantic upper low looks
to continue northwestward, opening up over the southeastern U.S. as
it is slowly absorbed into the larger upper trough moving eastward
early next week. Given the proximity of this feature and presence of
abundant moisture...expect scattered afternoon showers and storms
will remain possible through the weekend. Should the system track
well to the east of the Florida west coast, conditions may be drier
than currently forecast, as weak subsidence overspreads the
region.

Temperatures throughout the long range period look to remain in the
mid to upper 80s each afternoon, with lows in the upper 60s and
lower 70s most nights.

&&

.AVIATION...
24/07Z-25/06Z. VFR with FEW-SCT LCL BKN cumulus. Expect ISOLD
late afternoon TSRA/CB with best odds for LAL/PGD/FMY/RSW which
have VCNTY TSRA. Light mostly easterly winds...but shifting to
onshore at coastal terminals in the afternoon at 08KT or less.

&&

.MARINE...
High pressure moves out over the Western Atlantic by Wednesday then
extends back across northern FL to the Gulf for most of the week
with winds having an easterly component...but with occasional
afternoon sea breezes. Speeds run 15 knots of less although there
may be evening and late night surges up to 20 knots at times.

&&

.FIRE WEATHER...
Some drier air works in for the next 2 to 3 days with relative
humidity values briefly reach critical levels at a few mainly
northern locations. This dry air will be more limited across the
central and south where there could be some showers and thunder-
storms. increasing moisture will spread into the area for the end
of the week with higher RH values and chances of showers and
storms.

&&

.Preliminary Point Temps/PoPs...
TPA  88  71  89  69 /  10  10  10  10
FMY  89  71  88  69 /  40  20  20  20
GIF  89  69  87  67 /  10   0   0   0
SRQ  85  70  87  69 /  10  20  10  10
BKV  89  65  88  62 /  10   0  10   0
SPG  87  73  88  72 /  10  20  10  10

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WEATHER...09/Rude
MID TERM/LONG TERM/DECISION SUPPORT...84/Austin





000
FXUS62 KTBW 240045
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
845 PM EDT MON MAY 23 2016

.UPDATE (Rest of tonight)...
A few showers noted on 88D returns over southeast Highlands county
early this evening along the sea breeze/outflow boundaries will be
dissipating or moving out of the forecast area within the next
hour or so with pleasant dry conditions under mostly clear skies
expected the rest of tonight. Will wait until this convection ends
or exits east...then will update to the zones to remove evening
rain chances for interior locations. Other than this no other grid
or zone changes planned at this time.

&&

.AVIATION...
VFR will prevail at all terminal sites through 18Z on Tuesday.
After 18Z a few late afternoon thunderstorms will be possible
along the inland moving sea breeze with best chances at
KLAL...KPGD...KFMY...and KRSW terminals where VCTS has been
included...otherwise VFR will continue. West to northwest winds at
6 to 8 knots early this evening will become light and variable
after 02Z as the sea breeze circulation breaks down. East to
southeast winds at 5 to 7 knots after 14z on Tuesday will become
west to northwest at 7 to 9 knots at all coastal terminals after
18Z as the west coast sea breeze develops.

&&

.MARINE...
Onshore sea breeze component will collapse in the next hour or so
with loss of daytime heating with a light northeast to east flow
returning to the waters overnight as surface high pressure remains
across the northern peninsula and northeast Gulf. A weak pressure
pattern will again support an onshore sea breeze component
developing along the coast during Tuesday afternoon. Ongoing
forecast is in great shape...with no changes expected in the next
forecast issuance around 10 PM.

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

UPDATE/AVIATION/MARINE...57/McMichael
UPPER AIR...007/Dougherty
DECISION SUPPORT...03/Paxton





000
FXUS62 KTBW 232345
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
745 PM EDT MON MAY 23 2016

.AVIATION...
VFR will continue at all terminals through 18Z on Tuesday.
After 18Z a few late afternoon tsra may develop along the
inland moving sea breeze with best chances for tsra at KLAL
KPGD...KFMY...and KRSW terminals after 20Z where VCTS has been
introduced...otherwise VFR will continue. West to northwest
winds at 8 to 10 knots early this evening will become variable
less than 5 knots after 02Z. East to southeast winds at 4 to 6
knots are expected after 14Z except becoming West to northwest
at 8 to 10 knots at all coastal terminals as the west coast sea
breeze develops and moves inland.


&&

.Prev Discussion... /issued 346 PM EDT MON MAY 23 2016/

SYNOPSIS...
19Z water vapor and H4 RAP analysis showing an amplified upper
level pattern over the eastern half of the conus. The two main
features include sharp ridging extending from the lower MS valley
to the Great Lakes/SE Canada. This ridge has built west and north
of a large closed low spinning over the Mid-Atlantic coast. The
deep layer synoptic flow aloft between these two features is from
the west/NW over the Florida Peninsula...as sampled by the 12Z
KTBW RAOB. This flow is advecting plenty of mid/upper level dry
air down from the north...as also sampled by the 12Z RAOB and
shown clearly on latest WV imagery. A tight gradient in this upper
level moisture has been shifting southward through the day and is
now south of the Fort Myers area.

At the surface...old decaying frontal boundary has been quasi-
stationary over south Florida and combined with sea-breeze focus
is forcing a few thunderstorms down over the Everglades late this
afternoon. A few additional showers have developed east of Punta
Gorda ahead of the sea-breeze. Many hires guidance members have
been supportive of additional development over Highland County
into the evening hours...and this seems reasonable given the
predicted sea-breeze merger over this vicinity. Have increased
PoPs to 30-40% for this area through 00Z...with quickly
decreasing rain chances further north and west back toward the
coast.

Further north across the I-4 corridor and Nature coast...skies
become partly sunny through a sct cumulus field...however we are
now seeing a clearing line pushing inland behind the sea-breeze.
This region of clear skies should continue to expand inland from
the Nature and Suncoast the next several hours.

SHORT TERM (Tonight through Tuesday)...
Tonight...a generally dry forecast across the region. Upper
pattern evolves to become more cyclonic in nature over the
peninsula...however with the dry air aloft and loss of any sea-
breeze focus...should not be able to support much in the way of
convection...even over the far southern and interior southern
zones. During the early/mid evening hours before the sea-breeze
boundaries decay...a few lingering storms are possible in the
vicinity of Highlands County...but these should dissipate by
02-03Z. Low temperatures will end up a bit "cool" for late
May...as many spots drop down into the 60s by dawn...and even a
few normally colder spots possibly dropping to around 60 across
the Nature Coast.

Tuesday...
The region continues under broad troughing aloft with periodic
very weak impulses passing by...while at the surface...high
pressure ridges back to the west from off the SE conus coast into
the northern FL peninsula/NE Gulf of mexico. North of the I-4
corridor...the dry air aloft looks to be simply too dominant...and
have a dry forecast through the day.

The further south from the I-4 corridor one travels...a few late
afternoon storms appear likely...supported by a bit more column
moisture below 15kft seen on time-height forecast off the
NAM/GFS...along with lowered heights/cyclonic flow aloft...and
defined sea-breeze convergence. Afternoon forecast package did end
up raising PoPs somewhat for the second half of Tuesday afternoon.
Based on latest guidance ensemble...can not rule out a very
isolated shower for Polk/inland eastern Hillsborough county and
added a 20% PoP to the grids. Further south across the suncoast
and interior south-central zones...bumped rain chances up into
the 30-50% range...with the highest potential across Charlotte and
Lee counties. Temperatures once again will be seasonable... with
highs within a couple degrees of 90 inland...and into the 80s at
the beaches.

Mid/Long Term (Wednesday Night through Sunday)...
Models continue in good agreement through the work week then start
to diverge over the weekend. Main upper trough in the Western
Atlantic continues to pull off to the the NE through mid-week as
upper ridging from the W Gulf through the Mississippi River valley
into the Great Lakes region slowly shifts eastward. Meanwhile weak
remnant southern end of the trough detaches becoming a very weak
closed low meandering over the Bahamas at the end of the week. This
upper pattern will keep a dry NW aloft over the region for
minimal rain chances. At the surface, Western Atlantic Bermuda high
pressure extends into the Deep South with low level flow becoming
easterly. Temperatures to hold around normal through the week with
surface dew points increasing.

For the weekend, model uncertainties abound, and GFS seems be the
outlier, So, will go with a blend of the other more conservative
long range model solutions and expect the weak upper low/troughiness
near the Bahamas to remain weak as it drifts northward under upper
ridging. A weak surface reflexion in the form of a inverted trough
or very weak surface low center to develop, slowly move in a
northward direction and remain east of our forecast area to end the
weekend and into early next week. With this scenario the area would
be in a mainly dry/subsidence regime, but if the system doesn`t
materialize the area would return to more normal early summertime
diurnal seabreeze convective pattern. Temperatures to to range from
near normal to warm and slightly above normal conditions.

MARINE...
High pressure will ridge back to the west over northern Florida
and the northeast Gulf of Mexico through much of the the upcoming
week. Beginning Tuesday night and again Wednesday and Thursday
night...easterly surges of winds after sunset may approach 15
knots...and will settle down by mid-late morning each day.

FIRE WEATHER...
High pressure will remain stretched across the northern half
of the state through midweek. Relative humidity may briefly
drop into the upper 30s away from the coast Tuesday and Wednesday
afternoons...however no significant areas of critical relative
humidity are anticipated. Increasing low level moisture should
begin to reach the region toward the end of the week. Afternoon
and evening showers and thunderstorms will be at greatest risk
through Wednesday to the south of the I-4 corridor.

FOG POTENTIAL...No significant fog is expected through at least
Wednesday.

&&

.Preliminary Point Temps/PoPs...
TPA  70  89  71  90 /   0  10  10  10
FMY  69  89  70  90 /   0  40  20  20
GIF  67  88  69  89 /  10  20  10   0
SRQ  71  83  70  88 /   0  20  20  10
BKV  64  88  64  89 /   0  10  10   0
SPG  71  88  73  89 /   0  10  10  10

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

Aviation...57/McMichael





000
FXUS62 KTBW 231128 CCA
AFDTBW

Area Forecast Discussion...Corrected
National Weather Service Tampa Bay Ruskin FL
727 AM EDT MON MAY 23 2016

.AVIATION (23/12Z through 24/12Z)...
A few light showers/sprinkles at KPGD/KFMY/KRSW through mid-
morning with no cig or vis restrictions expected. Otherwise VFR
conditions are expected through the period for all TAFS. Light
winds will become westerly at 8-11kts this afternoon, then become
light and variable again with a few hours after sunset.

&&

.Prev Discussion... /issued 345 AM EDT MON MAY 23 2016/

SHORT TERM (Today-Tuesday)...
A weak cold front will continue to push south through the area
through the early morning hours with a few sprinkles possible
south of Tampa Bay. High pressure will be building into the area
today with drier air moving in as well. Aloft, an upper low will
be moving offshore of the mid-Atlantic states today and lift
northeast through Tuesday as upper ridging builds over the western
Gulf of Mexico. Surface high pressure will continue across the
area through Tuesday with winds shifting to the east as ridging
builds across from the Atlantic. This will allow moisture to start
to moderate and may allow for an isolated shower/thunderstorm
across the southern half of the area Tuesday afternoon along sea
breeze and outflow boundaries. Highs this afternoon will be in the
mid 80s near the coast to the upper 80s inland. Lows tonight will
be in the lower to mid 60s north, to the mid 60s to lower 70s
central and south. Highs Tuesday afternoon will be in the upper
80s to lower 90s.

LONG TERM (Tuesday night through Sunday)...
Initially ridging aloft reaches from the western Gulf to the Great Lakes
while an upper level closed low on the New England coast troughs south
down to the Bahamas. At the surface Atlantic high pressure broadly
ridges along 30 north latitude to the central Gulf. Through the end of
the week the upper ridge pivots from the Gulf to the eastern seaboard as
the low exits to the Canadian maritimes but leaves weak troughiness over
or east of the Bahamas. The surface ridge axis lifts north to the Mid-
Atlantic coast. A stable and dry air mass prevails with model PWAT values
running at or below 1 inch. Although moisture begins to increase Fri
with PWAT values of 1 to 1.25 inches spreading into southern then central
counties. With that in mind will keep the forecast dry until fri afternoon.
Then there will be a chance of showers/storms in the south with only a
slight chance for some central locations. temperatures run just under to
near normal.

For the weekend - upper level ridging generally continues from the Gulf
to the New England coast. As for the troughiness near the Bahamas - the
ECMWF...and the Canadian for early in the weekend...keeps a broad trough
or low near and east of the Bahamas. The GFS strengths it and slides it
north toward the southeast U.S. coast. Atlantic high pressure continues to
ridge westward across the Mid-Atlantic coast as an inverted trough forms
on it/s south side...east of the Bahamas in the ECMWF (and at the
end of the Canadian run) solution but north of there in the GFS
solution which is also a bit more robust. Moisture increases over
the weekend with GFS PWAT values 1 to 1.6 inches Sat and 1.4 to
1.9 inches Sun. However the ECMWF is drier and will go no higher
than mid-range chance showers/storms. the higher chances will be
south and in the central interior. temperatures will be around
seasonable readings.

MARINE...
High pressure will be building into the area today as a weak cold
front exits the state to the south. High pressure will then be in
place across the waters through the week. Winds are expected to
remain AOB 15 knots and seas AOB 4 feet through the period.

FIRE WEATHER...
Drier air is in place across the northern half of the area and
will allow for a few hours of critical humidities across the
nature coast this afternoon. Winds will be below 15 mph and ERC
values below 37 so no headlines are expected. Moisture will
moderate for Tuesday and through the rest of the week.

&&

.Preliminary Point Temps/PoPs...
TPA  87  70  89  71 /   0   0  10   0
FMY  88  70  90  71 /  20   0  20  10
GIF  88  68  89  69 /  10  10  10  10
SRQ  86  67  89  70 /   0   0  10   0
BKV  88  60  89  64 /   0   0  10  10
SPG  86  72  88  73 /   0   0  10   0

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.

&&

$$

AVIATION...Mroczka
PREVIOUS DISCUSSION...Hubbard/Rude





000
FXUS62 KTBW 231127
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
727 AM EDT MON MAY 23 2016

.AVIATION (2312Z Through 24/12Z...
A few light showers/sprinkles at KPGD/KFMY/KRSW through mid-
morning with no cig or vis restrictions expected. Otherwise VFR
conditions are expected through the period for all TAFS. Light
winds will become westerly at 8-11kts this afternoon, then become
light and variable again with a few hours after sunset.

&&

.Prev Discussion... /issued 345 AM EDT MON MAY 23 2016/

SHORT TERM (Today-Tuesday)...
A weak cold front will continue to push south through the area
through the early morning hours with a few sprinkles possible
south of Tampa Bay. High pressure will be building into the area
today with drier air moving in as well. Aloft, an upper low will
be moving offshore of the mid-Atlantic states today and lift
northeast through Tuesday as upper ridging builds over the western
Gulf of Mexico. Surface high pressure will continue across the
area through Tuesday with winds shifting to the east as ridging
builds across from the Atlantic. This will allow moisture to start
to moderate and may allow for an isolated shower/thunderstorm
across the southern half of the area Tuesday afternoon along sea
breeze and outflow boundaries. Highs this afternoon will be in the
mid 80s near the coast to the upper 80s inland. Lows tonight will
be in the lower to mid 60s north, to the mid 60s to lower 70s
central and south. Highs Tuesday afternoon will be in the upper
80s to lower 90s.

LONG TERM (Tuesday night through Sunday)...
Initially ridging aloft reaches from the western Gulf to the Great Lakes
while an upper level closed low on the New England coast troughs south
down to the Bahamas. At the surface Atlantic high pressure broadly
ridges along 30 north latitude to the central Gulf. Through the end of
the week the upper ridge pivots from the Gulf to the eastern seaboard as
the low exits to the Canadian maritimes but leaves weak troughiness over
or east of the Bahamas. The surface ridge axis lifts north to the Mid-
Atlantic coast. A stable and dry air mass prevails with model PWAT values
running at or below 1 inch. Although moisture begins to increase Fri
with PWAT values of 1 to 1.25 inches spreading into southern then central
counties. With that in mind will keep the forecast dry until fri afternoon.
Then there will be a chance of showers/storms in the south with only a
slight chance for some central locations. temperatures run just under to
near normal.

For the weekend - upper level ridging generally continues from the Gulf
to the New England coast. As for the troughiness near the Bahamas - the
ECMWF...and the Canadian for early in the weekend...keeps a broad trough
or low near and east of the Bahamas. The GFS strengths it and slides it
north toward the southeast U.S. coast. Atlantic high pressure continues to
ridge westward across the Mid-Atlantic coast as an inverted trough forms
on it/s south side...east of the Bahamas in the ECMWF (and at the
end of the Canadian run) solution but north of there in the GFS
solution which is also a bit more robust. Moisture increases over
the weekend with GFS PWAT values 1 to 1.6 inches Sat and 1.4 to
1.9 inches Sun. However the ECMWF is drier and will go no higher
than mid-range chance showers/storms. the higher chances will be
south and in the central interior. temperatures will be around
seasonable readings.

MARINE...
High pressure will be building into the area today as a weak cold
front exits the state to the south. High pressure will then be in
place across the waters through the week. Winds are expected to
remain AOB 15 knots and seas AOB 4 feet through the period.

FIRE WEATHER...
Drier air is in place across the northern half of the area and
will allow for a few hours of critical humidities across the
nature coast this afternoon. Winds will be below 15 mph and ERC
values below 37 so no headlines are expected. Moisture will
moderate for Tuesday and through the rest of the week.

&&

.Preliminary Point Temps/PoPs...
TPA  87  70  89  71 /   0   0  10   0
FMY  88  70  90  71 /  20   0  20  10
GIF  88  68  89  69 /  10  10  10  10
SRQ  86  67  89  70 /   0   0  10   0
BKV  88  60  89  64 /   0   0  10  10
SPG  86  72  88  73 /   0   0  10   0

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.

&&

$$

AVIATION...Mroczka
PREVIOUS DISCUSSION...Hubbard/Rude





000
FXUS62 KTBW 230553
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
153 AM EDT MON MAY 23 2016

.AVIATION...
A few sprinkles are possible at KPGD over the next hour or two.
otherwise VFR conditions are expected through the period. Light
winds will become westerly at 8-10kts this afternoon, then become
light and variable again after sunset.

&&

.Prev Discussion... /issued 915 PM EDT SUN MAY 22 2016/

UPDATE (Rest of tonight)...High clouds and a stray shower continue
to stream in from a convective complex located in the central Gulf
of Mexico. This complex will weaken overnight so not expecting any
significant weather through the night. High pressure will move into
the area on Monday allowing for dry but warm conditions.
Temperatures will remain just around average for this time of year
with overnight lows in the upper 60s to mid 70s.

AVIATION...VFR conditions along with west northwest winds at 5-10
knots will continue for the next several hours, then decreasing to
around 5 knots early Monday morning. A stray shower may move onshore
near FMY/RSW, but not expected to bring conditions below VFR. No
other impacts expected through the period.

MARINE...High pressure moving into the area will keep winds out of
the west northwest less than 15 knots through Monday morning. For
the beginning of next week, the winds will vary from the northwest
to northeast and remain light around 10 knots. The high shifts east
into the western Atlantic by mid week allowing for the winds to veer
to the east through the end of next week. No significant rainfall or
storms are expected through the next 5 days.

&&

.Preliminary Point Temps/PoPs...
TPA  87  69  88  73 /   0   0  10   0
FMY  88  69  90  71 /  10  10  20  10
GIF  89  66  91  70 /   0   0  10   0
SRQ  85  69  83  71 /   0   0  10   0
BKV  87  63  89  68 /   0   0  10   0
SPG  86  71  88  73 /   0   0  10   0

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

SHORT TERM/AVIATION/MARINE/FIRE WEATHER...24/Hubbard
MID TERM/LONG TERM/DECISION SUPPORT...09/Rude





000
FXUS62 KTBW 222335
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
735 PM EDT SUN MAY 22 2016

.AVIATION...VFR conditions along with west northwest winds at 5-10
knots will continue for the next several hours, then decreasing
to around 5 knots early Monday morning. A stray shower may move
onshore near FMY/RSW, but not expected to bring conditions below
VFR. No other impacts expected through the period.

&&

.Prev Discussion... /issued 249 PM EDT SUN MAY 22 2016/

SHORT TERM (Tonight-Monday)...
Upper low sinking down the Eastern Seaboard tonight and spinning
over the Carolinas tomorrow. Combination of features to wrap
around this low with dry slot from the mid Mississippi River
valley into the Deep South and N FL tonight into Mon. Also, the
convective complex over the Central Gulf this afternoon to bring
thick cirrus clouds over the C and S FL Peninsula this evening and
tonight with a slight chance of precip over extreme southern
marine and land zones overnight into Monday. The weak front moving
down the state this afternoon to continue and sink south tonight
then pull off into the Atlantic Monday as weak high pressure
builds into the region. Expect mostly cloudy skies to keep temps
at or slightly above climo from the Bay Area into SW FL with
partly cloudy and slightly cooler conditions over the Nature Coast
tonight. Drier and mostly sunny conditions are expected for most
of the area Monday with daytime temps around seasonal norms.

Mid/Long Term (Monday through next Saturday)...
The forecast philosophy for the middle and later portion of the week
has not changed over the past several forecast cycles. Global
guidance continues to indicate quite a dry and generally suppressive
tropospheric column in place over the Florida peninsula through at
least Thursday. Very little in the way of synoptic forcing as well
as the region remains between a large closed low over the eastern
seaboard...and ridging in the mid/upper levels over the
western/central Gulf of Mexico.

With these features in place...would anticipate a generally dry
forecast. Closer to the moisture gradient down over far south
Florida...did allow for a 20% chance of a shower or storm around the
Fort Myers area late Tuesday afternoon...but any convection will be
isolated in nature. Wednesday and Thursday felt confident in keeping
the entire forecast area dry.

Temperatures through the middle of the week look seasonable during
the day...and a bit below normal at night due to the drier air in
place.

Atmospheric moisture should begin to slowly recover as we head into
Friday and especially Saturday. Given the time of year and the
increasing moisture/less hostile environment toward deep
convection...will allow for low/chance PoPs to reenter the forecast
each afternoon/evening. A low level 1000-700mb synoptic flow out of
the east would also favor the western side of the state for sea-
breeze convection. However...given how the wet season is still not
really in full effect...and the atmospheric moisture will be slow to
recover...will keep PoPs lower than would normally be expected with
a similar flow regime.

Daytime temperatures remain seasonable with overnight lows returning
to climo norms as well.

AVIATION...
VFR conditions continue as gusty westerly winds diminish quickly
after sunset and large thick cirrus deck advects and holds over
region tonight.

MARINE...
Slightly tight pressure gradient and seabreeze surge to keep
winds in 10-15 kt range rest of today into tonight with seas
around 2-3 ft range with a moderate chop. Gradient relaxes Mon-
Tue as high pressure moves over the region and into the Western
Atlantic. Winds veer E-SE as Bermuda high becomes entrenched with
afternoon sea breezes each day through the week.

FIRE WEATHER...
Drier air over the region to produce several hours of critical
humidities Monday but conditions expected to remain below red flag
criteria as ERC values are low. Low level moisture to slowly
return beginning Tuesday continuing through the week with no
significant fire weather concerns.

&&

.Preliminary Point Temps/PoPs...
TPA  71  87  69  88 /   0   0   0  10
FMY  72  88  69  90 /  10  10  10  20
GIF  67  89  66  91 /   0   0   0  10
SRQ  70  85  69  83 /   0   0   0  10
BKV  61  87  63  89 /   0   0   0  10
SPG  73  86  71  88 /   0   0   0  10

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

AVIATION...74/Wynn





000
FXUS62 KTBW 221849
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
249 PM EDT SUN MAY 22 2016

.SHORT TERM (Tonight-Monday)...
Upper low sinking down the Eastern Seaboard tonight and spinning
over the Carolinas tomorrow. Combination of features to wrap
around this low with dry slot from the mid Mississippi River
valley into the Deep South and N FL tonight into Mon. Also, the
convective complex over the Central Gulf this afternoon to bring
thick cirrus clouds over the C and S FL Peninsula this evening and
tonight with a slight chance of precip over extreme southern
marine and land zones overnight into Monday. The weak front moving
down the state this afternoon to continue and sink south tonight
then pull off into the Atlantic Monday as weak high pressure
builds into the region. Expect mostly cloudy skies to keep temps
at or slightly above climo from the Bay Area into SW FL with
partly cloudy and slightly cooler conditions over the Nature Coast
tonight. Drier and mostly sunny conditions are expected for most
of the area Monday with daytime temps around seasonal norms.

.Mid/Long Term (Monday through next Saturday)...
The forecast philosophy for the middle and later portion of the week
has not changed over the past several forecast cycles. Global
guidance continues to indicate quite a dry and generally suppressive
tropospheric column in place over the Florida peninsula through at
least Thursday. Very little in the way of synoptic forcing as well
as the region remains between a large closed low over the eastern
seaboard...and ridging in the mid/upper levels over the
western/central Gulf of Mexico.

With these features in place...would anticipate a generally dry
forecast. Closer to the moisture gradient down over far south
Florida...did allow for a 20% chance of a shower or storm around the
Fort Myers area late Tuesday afternoon...but any convection will be
isolated in nature. Wednesday and Thursday felt confident in keeping
the entire forecast area dry.

Temperatures through the middle of the week look seasonable during
the day...and a bit below normal at night due to the drier air in
place.

Atmospheric moisture should begin to slowly recover as we head into
Friday and especially Saturday. Given the time of year and the
increasing moisture/less hostile environment toward deep
convection...will allow for low/chance PoPs to reenter the forecast
each afternoon/evening. A low level 1000-700mb synoptic flow out of
the east would also favor the western side of the state for sea-
breeze convection. However...given how the wet season is still not
really in full effect...and the atmospheric moisture will be slow to
recover...will keep PoPs lower than would normally be expected with
a similar flow regime.

Daytime temperatures remain seasonable with overnight lows returning
to climo norms as well.

&&

.AVIATION...
VFR conditions continue as gusty westerly winds diminish quickly
after sunset and large thick cirrus deck advects and holds over
region tonight.

&&

.MARINE...
Slightly tight pressure gradient and seabreeze surge to keep
winds in 10-15 kt range rest of today into tonight with seas
around 2-3 ft range with a moderate chop. Gradient relaxes Mon-
Tue as high pressure moves over the region and into the Western
Atlantic. Winds veer E-SE as Bermuda high becomes entrenched with
afternoon sea breezes each day through the week.

&&

.FIRE WEATHER...
Drier air over the region to produce several hours of critical
humidities Monday but conditions expected to remain below red flag
criteria as ERC values are low. Low level moisture to slowly
return beginning Tuesday continuing through the week with no
significant fire weather concerns.

&&

.Preliminary Point Temps/PoPs...
TPA  71  87  69  88 /   0   0   0  10
FMY  72  88  69  90 /  10  10  10  20
GIF  67  89  67  90 /   0   0   0  10
SRQ  70  85  68  86 /   0   0   0  10
BKV  61  87  59  90 /   0   0   0  10
SPG  73  86  72  87 /   0   0   0  10

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

SHORT TERM/AVIATION/MARINE/FIRE WEATHER...25/Davis
MID TERM/LONG TERM/DECISION SUPPORT...14/Mroczka





000
FXUS62 KTBW 221151
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
751 AM EDT SUN MAY 22 2016

.AVIATION...
Westerly flow and VFR conditions to continue today.

&&

.Prev Discussion... /issued 354 AM EDT SUN MAY 22 2016/

SHORT TERM (Today-Monday)...
Aloft, and upper trough/low will linger along the mid-Atlantic
states. A weak frontal boundary currently moving into northern
Florida will move through the area today before stalling across
south Florida. Drier air will move into the area behind the front
through Monday as surface high pressure builds in from the north.
No rain is expected through the period, but a sprinkle or two
might be possible as the front move through. Highs this afternoon
will be in the mid 80s to around 90. Lows tonight will range from
around 60 to the mid 60s north, and in the mid 60s to lower 70s
central and south.

LONG TERM (Monday night through Saturday)...
Mon night-Wed: An upper ridge from the western Gulf to the Great
Lakes slowly slides east and flattens some as a closed low initially
on the Mid-Atlantic coast tracks northeastward...to south of the
Canadian Maritimes. These feature maintain a generally dry and
stable northwest flow aloft the area. A weak and dry front exits the
state Mon night as high pressure builds in across Fl to the Gulf.
The front stalls then dissipates over or south of the Keys and may
provide limited showers or storms in far southern locations.
temperatures will run near to just below normal.

Late Wed-Sat: The upper ridge pivots out over the Atlantic from the
Gulf as a weak low forms over the Bahamas...this is more pronounced
in the GFS. The Atlantic surface ridge lifts up to the Mid-Atlantic
coast with prevailing easterly low level flow slowly increasing
moisture. This moisture along with some lift provided by the upper
low in the Atlantic will result in isolated to scattered showers and
storms that spread northward fri and sat. Temperatures will be near
normal.

AVIATION...
VFR conditions are expected through the period with WNW winds
increasing through the afternoon.

MARINE...
A frontal boundary will move through the area today with drier air
moving into the area behind the front. High pressure will build
over the region behind the front and remain in place through the
week. Winds and seas are expected to remain AOB 15 knots and 4
feet.

FIRE WEATHER...
Drier air will be moving into the area today, but RH values are
expected to remain above critical levels. Even drier conditions
are expected for Monday with a few hours of critical humidities
possible. ERC values are low however, so no headlines are
expected. Conditions will start to moderate for Tuesday, with an
hour or two of critical humidities possible mainly across the
Nature Coast.

&&

.Preliminary Point Temps/PoPs...
TPA  87  69  86  69 /  10   0   0   0
FMY  90  71  88  69 /  10   0  10  10
GIF  88  67  88  67 /   0   0   0   0
SRQ  86  69  86  68 /  10   0   0   0
BKV  87  61  87  59 /   0   0   0   0
SPG  86  72  86  72 /  10   0   0   0

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

AVIATION...25/Davis





000
FXUS62 KTBW 220027
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
827 PM EDT SAT MAY 21 2016

.UPDATE (Rest of tonight)...High pressure has moved into the
area allowing for skies to clear up nicely. Pleasant conditions can
be expected through the night as well. Temperatures will remain just
around average for this time of year with overnight lows in the
upper 60s to mid 70s.

&&

.AVIATION...VFR conditions along with west northwest winds at 8-12
knots will prevail through the period.

&&

.MARINE...High pressure moving into the area will keep winds out of
the west northwest less than 15 knots for the remainder of the
weekend. For the beginning of next week, the winds will vary from
the northwest to northeast and remain light around 10 knots. No
significant rainfall or storms are expected through the next 5 days.


&&

.Preliminary Point Temps/PoPs...
TPA  75  86  70  86 /  10  10   0   0
FMY  74  88  71  88 /  10  10   0  10
GIF  72  88  67  89 /  10  10   0   0
SRQ  74  85  71  81 /  10  10   0   0
BKV  68  87  63  86 /  10  10   0   0
SPG  75  86  72  86 /  10  10   0   0

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

UPDATE/AVIATION/MARINE...74/Wynn
UPPER AIR...007/Dougherty
DECISION SUPPORT...57/McMichael





000
FXUS62 KTBW 212329
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
729 PM EDT SAT MAY 21 2016

.AVIATION...VFR conditions along with west northwest winds at 8-12
knots will prevail through the period.

&&

.Prev Discussion... /issued 231 PM EDT SAT MAY 21 2016/

SHORT TERM (Tonight-SuNday)...Upper trough continues to slowly
move eastward to the east coast tonight becoming a closed low
over the Mid Atlantic region late Sunday. WNW flow aloft has
brought very dry mid-upper airmass over the northern half of the
FL Peninsula this afternoon through tonight. Narrow vort max from
Texas into the Central Gulf to bring upper clouds over the S
Florida Peninsula tonight. Weak frontal boundary over the Deep
South holds in place as surface storm system intensifies over the
Carolinas while weak high pressure holds through the FL Straits
keeping westerly low level flow in place for warm and muggy
overnight conditions in place.

Potent shortwave and vort max to rotate around upper low Sunday to
push surface front through the region but moisture will be limited
so expect the front to come through mainly dry. High pressure
and drier airmass to build into the region late Sunday while
daytime temp hold around seasonal normals.

MID/LONG TERM (Monday through next Saturday)... The synoptic
pattern for a majority of the middle and longer term forecast
period will favor benign sensible weather for the end of May.
Based on the forecast pattern by the global guidance
ensembles...the summer rainy season will hold off for at least
another week.

The upcoming work wee will start off with an amplified upper level
pattern across the eastern Conus...highlighted by a large closed
upper low spinning over the Eastern seaboard. Despite the generally
close proximity of this feature...our position on the backside of
the circulation will provide a steady supply of deep layer
subsidence/dry air advection aloft over the northern and central
Florida Peninsula.

This synoptic setup will favor a generally dry forecast through at
least Thursday...with any real chances for diurnal showers staying
across far southeast/southern portion of the Peninsula. A few
isolated storms may be possible any of these days across Lee or
Highlands counties...however...really appears better PoPs will stay
a bit further to the south.

Late in the period as we head into Friday and especially
Saturday...a modest increase in column moisture and the arrival of
at least subtle high level support for lift should result in renewed
potential for sct diurnal convection to work back northward into
west-central parts of the peninsula.

Temperatures looking to be perhaps a few degrees below normal for
Monday through Wednesday...although still seasonable. Temperatures
returning to near normal for the end of the week.

AVIATION...
Dry westerly flow to keep VFR conditions over all terminals through
Sunday.

MARINE...
Gradient between frontal boundary in the Deep South and high pressure
in the FL Straits to produce light to moderate westerly winds
tonight through Monday. Seas are expected to run 2-3 ft or less.
Weak high pressure moves into the Western Atlantic extending back
into the area with winds becoming easterly Tuesday through midweek
with afternoon seabreezes.

FIRE WEATHER...
Warm and humid conditions will continue this weekend. A front will pass
over the region Sunday with much drier conditions for the start of
the new week. Afternoon RHs may briefly drop below 35 percent Monday.

Fog Potential...Significant fog is not expected tonight.

&&

.Preliminary Point Temps/PoPs...
TPA  75  86  70  86 /  10  10   0   0
FMY  74  88  71  88 /  10  10   0  10
GIF  72  88  67  89 /  10  10   0   0
SRQ  74  85  71  81 /  10  10   0   0
BKV  68  87  63  86 /  10  10   0   0
SPG  75  86  72  86 /  10  10   0   0

&&

.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&

$$

AVIATION...74/Wynn





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