Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS62 KTBW 221920

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
320 PM EDT Tue May 22 2018

.SHORT TERM (Tonight through Wednesday)...
Little overall change through Wednesday as the eastern Gulf of
Mexico and Florida continue to reside underneath a broad cyclonic
flow pattern. Moisture has decreased slightly, precipitable water
between 1.7 and 1.9 inches, but still plenty when combined with
daytime heating and the sea breezes for a more typical coverage of
diurnal storms across the area. Locally heavy rainfall will continue
to be the main issue with minor flooding of low lying and poor
drainage areas possible. Low temperatures will be near normal
in the upper 60s to lower 70s while daytime highs are near
to slightly below normal in the mid to upper 80s.

.MID TERM/LONG TERM (Wednesday Night through next Tuesday)...
The main concerns for the long-term forecast period will continue to
be the potential for heavy rainfall along with localized flooding
and river flooding. A broad cyclonic flow will generally remain over
the region through early next week, with abundant deep tropical
moisture continuing to stream over the region. At the surface, the
subtropical ridge axis will extend across the northern Florida
peninsula, keeping a low-level southeast wind flow in place. For
both Thursday and Friday, we can expect scattered to numerous
showers and thunderstorms across the forecast area with a bit of a
break overnight, but likely still not totally dry.

As we head into the weekend, the threat for heavy rainfall and
flooding will remain as a disturbance lifts out of the Caribbean Sea
and into the central or eastern Gulf of Mexico on Saturday. This
disturbance is currently quite disorganized, so models are having a
hard time with its evolution over the next several days. The latest
GFS is farther east with its solution than the ECMWF, which takes
the system more into the central Gulf and into the MS/LA region. The
ECMWF is also about a day faster than the GFS. Having said all that,
regardless of timing or whether this system becomes tropical or not,
the impacts will continue to be a concern and those are more heavy
rain with additional flooding. Still several days to keep an eye on
the evolution of this system, but even a central Gulf track versus
an eastern Gulf track would not necessarily make that big of a
difference as far as impacts for our region. This system would have
to track farther west than is currently being shown to have a
diminishing heavy rainfall threat for us.

For early next week, global models continue to show cyclonic flow
over the region with continued deep moisture over the region, so the
threat for additional rainfall looks to remain.


Some areas of MVFR ceilings will be possible this morning, then
scattered to numerous showers and thunderstorms are expected this
afternoon which could cause some more MVFR/local IFR conditions
along with gusty winds up to around 30 knots. Convection will wind
down this evening with mainly VFR conditions overnight followed by a
repeat of today on Wednesday.


Southeast flow will continue at 15 knots or less for the next few
days with the west coast sea breeze trying to develop each afternoon
through Thursday. Winds and seas will remain below advisory levels
through Thursday with the main hazard continuing to be the scattered
showers and thunderstorms with some of the stronger storms capable
of producing strong gusty winds and locally rough seas. Late in the
week winds and seas could increase to near advisory levels, but this
all depends on the evolution and movement of the area of low
pressure moving out of the western Caribbean Sea.


No fire weather hazards are expected for the next several days as
relative humidity values are expected to remain well above critical


.Preliminary Point Temps/PoPs...
TPA  72  88  74  86 /  30  40  30  60
FMY  72  89  72  87 /  20  70  30  60
GIF  71  89  72  88 /  20  50  20  60
SRQ  72  87  73  85 /  20  40  30  50
BKV  69  89  71  88 /  30  40  40  50
SPG  75  87  75  86 /  30  40  30  60


Gulf waters...None.


MID TERM/LONG TERM/DECISION SUPPORT...05/Carlisle is the U.S. government's official web portal to all federal, state and local government web resources and services.