Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL

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FXUS62 KTBW 291841

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
241 PM EDT Mon May 29 2017

.SHORT TERM (Tonight - Tuesday)...
Mid level high pressure centered east of the state today is
continuing to ridge across the area, but will gradually slip east
and away tonight and Tuesday. At the surface, the sub tropical ridge
will gradually lift north across the Florida Peninsula through
Tuesday, with light low level flow becoming increasingly southerly.
This will lead to atmospheric moisture increasing by Tuesday
afternoon. This increased moisture, combined with reduced ridging
aloft will allow for better chances of showers and thunderstorms
Tuesday afternoon, along sea breeze boundaries. From the Tampa Bay
north, the best storm chances will be well inland, but to the south
of Tampa Bay, the sea breeze collision will be focused closer to the
west coast.

With higher humidity and increased cloud cover on Tuesday,
temperatures are not expected to be quite as hot as today, but will
still be a few degrees above normal. High temperatures Tuesday
afternoon are expected to run in the mid 90s inland, and in the
upper 80s and low 90s near the coast.

.Long Term (Wednesday through next Monday)...
The middle and end of the week are looking fairly typical in terms
of pattern and forecast for early June. The main upper ridge will
have shifted to the east and southeast resulting in less overall
large-scale suppression and a higher degree of atmospheric moisture.
Over time the large scale low level flow will become S/SE as the
surface ridge axis shift to the northern half of the peninsula. This
flow, when moisture is present is often an active pattern for
diurnal sea-breeze storms. The forecast will be ramping up the rain
chances to account for this greater storm potential, but remember
that even though rain is in the forecast, we are talking about late
in the day...and generally brief durations of actual rainfall.

During next weekend, there remains some disagreement in the degree
and speed to which mid/upper level troughing will dig out of the
southern plains into the northern Gulf. Latest GFS/Canadian are more
aggressive with this amplification compared to the ECMWF which holds
a greater degree of ridging (especially over the eastern
Gulf/Florida). The more and faster this trough digs, the faster our
low level flow will shift more from the southwest. The southwest
flow this time of year would push the greater thunderstorm coverage
further inland. However, many of the global models are suggesting an
upper level disturbance may get caught up in this amplification and
move northeastward across the Gulf/SE Conus. This disturbance would
bring a greater potential for synoptic rainfall. So...the confidence
in the forecast next weekend is below normal. A good generalization
would be to say, the further into the weekend we get, the greater
chances for a more cloudy and showery forecast will develop.

Still have plenty of time to watch the guidance trends and revise
the current forecast over the coming days.


A few isolated spots of MVFR ceilings are persisting over the area,
but otherwise VFR conditions will continue into this evening. Patchy
fog tonight is expected mostly north of the Tampa Bay terminals, but
isolated periods of reduced flight categories cannot be entirely
ruled out at area terminals.


Surface high pressure will continue to ridge from the Atlantic into
the eastern Gulf of Mexico through the next few days, with light and
rather variable winds turning onshore each afternoon with the sea
breeze. Winds and seas will remain below headline criteria.


Moisture is continuing to increase across the state. Relative
humidity will approach 35 percent for a couple hours during the next
few afternoons, mainly over interior regions. Some patchy fog will
be possible again Tuesday morning, mainly over the Nature Coast.


.Preliminary Point Temps/PoPs...
TPA  76  91  77  91 /   0  20  10  40
FMY  75  92  75  92 /  10  30  20  50
GIF  74  95  74  94 /  10  40  30  50
SRQ  74  87  75  87 /   0  10  10  30
BKV  71  92  72  92 /   0  20  10  40
SPG  76  91  77  91 /   0  10  10  30


Gulf waters...None.


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