High resolution image of Tampa Bay region
The
Tampa Bay
area
has a humid
subtropical climate (Koppen Cfa), with warm
temperatures and the threat of thunderstorms during the summer and the winter frost about every 2-3 years. Tampa
itself experiences a summer wet season, where nearly two-thirds of the annual
precipitation falls in
the months of June through September. The area is listed by
the United States Department of Agriculture
as being in hardiness zone
10, which is about the northern limit of where coconut palms and royal
palms can be grown. Highs usually range between 65 and
95
°F (18 and 35
°C) year round.
Surprisingly to some, Tampa's
official high has never reached 100 °F (38 °C) –
the all-time record high temperature is 99 °F (37 °C).
St.
Petersburg's
all-time record high is exactly 100 °F (38
°C).
Pinellas
County
lies on a peninsula
between Tampa
Bay
and the Gulf of Mexico
, and much of the city of Tampa lies on a smaller
peninsula jutting out into Tampa Bay. This proximity to
large bodies of water both moderates local temperatures and
introduces large amounts of
humidity into
the atmosphere. In general, the communities farthest from the coast
have more extreme temperature differences, both during a single day
and throughout the
seasons of the
year.
Seasonal weather
Precipitation trends
Because of frequent summer
thunderstorms, Tampa has a pronounced
wet season, receiving an average of about of rain
from June and September but only about during the remaining eight
months of the year. The historical averages during the late summer,
especially September, are augmented by
tropical cyclones, which can easily deposit
many inches of rain in one day. Outside of the summer rainy season,
most of the area's precipitation is delivered by the occasional
passage of a
weather front.
Tampa's
precipitation
data falls near the median for the area. Nearby communities to the
interior tend to receive a bit more rain every year; those closer
to the coast a bit less.

The 1977 snowfall
Winter
In the winter, the low temperature in the Tampa Bay area rarely
drops below freezing , an occurrence which happens, on average,
once every other year. Since the area is home to a diverse range of
freeze-sensitive
agriculture and
aquaculture, cold snaps are a
significant concern. The lowest temperature ever recorded in Tampa
was 18 °F (-7.8 °C) on December 13, 1962. Usually, winter highs are
near with sunny skies. The occasional passage of a
cold front will bring rain followed by a few days
of cooler temperatures.
Frozen precipitation is very rare in the area. In the
Great Blizzard of 1899, Tampa
suffered its one and only known
blizzard,
with
"bay effect" snow coming off
Tampa Bay. The last officially measurable snow in Tampa fell on
January 19, 1977. The accumulation amounted to only . Many
residents of southern Pinellas County reported a light snowfall
during a record cold snap on December 23, 1989. However, no snow
fell at official weather stations, and the official weather record
indicates that
sleet fell on St.
Petersburg that day.
Spring
Spring in the Tampa area is usually mild and dry, with highs in the
70s (around 25 C) and lows in the 50s (around 13 C).
However, the calm is occasionally disturbed by the arrival of
late-season cold fronts. The clash of a strong cold front against
warm and humid local air can cause
squall line to develop and cause wind
damage across the area. The most dramatic example of this was the
Storm of the Century in
1993, but other smaller-scale events (such as the storm which
caused a
freighter to strike and partially
collapse the original
Sunshine
Skyway bridge in May 1980) occur every few years.
Summer
Temperatures are hot from around mid-May through mid-October, which
coincides approximately with the rainy season. Summertime weather
is very consistent, with highs in the low 90s °F (around 32 °C),
lows in the mid-70s °F (around 24 °C), accompanied by high
humidity and an almost daily chance of afternoon
thundershowers.
The
typical summer weather pattern is for heat-produced thermals, powered by either the Gulf or Atlantic
sea breeze (and
occasionally both simultaneously), to build puffy white cumulus clouds into threatening thunderheads over the interior of the Florida
peninsula. Usually, the resulting storms drift slowly
westward to the bay area, though they may rain themselves out
before reaching Tampa if the easterly winds are light or the
sea breeze from the Gulf of Mexico
is too strong. Occasionally, the storms
survive to move out over the Gulf of Mexico, where they can be seen
at night from the beaches as spectacular light shows.
The afternoon storms typically bring brief periods of heavy
rain with frequent cloud-to-ground
lightning, and are usually followed by a
pleasantly clear and cooler evening. At times, they can grow
severe, bringing gusty winds,
small
hail, and torrential rain. Strong
tornadoes are rare, but do occur
occasionally. While Florida does rank #1 in the USA in terms of
tornadoes per square mile, the majority of the twisters as small,
weak, and short-lived . Waterspouts occur in the Tampa Bay and off
the Gulf Coast quite frequently during summer thunderstorms and
will occasionally move on-shore as a weak tornado.
Though the Tampa Bay area is sometimes referred to as the
"Lightning Capital of the World", it is actually the “Lightning
Capital of North America” if measured by average number of days
with
thunderstorm activity per year.
West-Central Florida receives as much
lightning during its rainy season as the world’s maximum
thunderstorm areas such as the Lake Victoria
region of Africa and the
central Amazon River Basin, but
the local lightning rate tails off significantly as temperatures
cool in the fall, decreasing the yearly average.
Every year, Florida averages 10 deaths and 30 injuries from
lightning strikes, with several of these usually occurring in or
around Tampa.
University of Florida
lightning expert Martin
A. Uman has calculated
that the average resident is within a half-mile of 10 to 15
lightning strikes every year.
TECO
Energy, the local electric utility, spends almost USD
$1,000,000 annually to repair
transformers and other equipment damaged by
lightning strikes.
Hurricanes
June through November is
hurricane season in the
Atlantic Basin, with the most tropical
activity occurring between mid-August to mid-October.
Rain dropped by
tropical
systems is an important component of the area's annual
precipitation and is vital for
replenishing the water supply of communities around Tampa
Bay.
The area feels some effect from passing tropical systems almost
every year, but
direct hits
are uncommon. Estimates of the probability of a hurricane making
landfall in the Tampa Bay area during any given year range from 1
in 25 to 1 in 50. While the historical record has shown that the
area is vulnerable to a large storm (such as the
Great Gale of 1848), Tampa Bay has not
seen the landfall of any hurricane since 1946, and has not taken a
hit from a major hurricane since
1921.
The 2004 Tropical Season
The
2004 Atlantic
Hurricane Season was historically busy for the Tampa Bay area.
The region was affected by a record four hurricanes that year;
Frances,
Jeanne,
Charley, and to a lesser extent,
Ivan. Jeanne and Frances passed over Tampa as
tropical storms after making their way across the state from the
east coast. Charley was forecast to make a direct hit on Tampa Bay
from the south-southwest, which would have been the worst-case
scenario for local
storm surge flooding.
But the
storm made a sudden and unexpected turn to the northeast and
brought only tropical storm force winds to the region, devastating
the Ft.
Myers
/Port Charlotte
area instead. Ivan also threatened
the area as it moved north up the eastern Gulf of Mexico
. It remained far to the west of central
Florida, however, and brought only a bit of rain and wind to Tampa
Bay before eventually slamming into coastal Alabama
and the Florida
Panhandle.
Autumn
Both
temperature and
rainfall start a downward trend
in early to mid-October as the weather in Tampa turns drier and
calm. However, the hurricane season extends until the end of
November, and the area is sometimes affected by a hurricane or
tropical storm during the fall.
Monthly Climate Summary
Tampa
St. Petersburg
| Month |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Year |
| Rec high °F
(°C) |
87
(30) |
86
(30) |
90
(32) |
93
(33) |
96
(35) |
100
(37) |
99
(37) |
97
(36) |
97
(36) |
94
(34) |
90
(32) |
89
(31) |
100
(37) |
| Avg high °F
(°C) |
70
(21) |
71
(21) |
76
(24) |
81
(27) |
86
(30) |
89
(31) |
90
(32) |
90
(32) |
89
(31) |
84
(28) |
77
(25) |
72
(22) |
81
(27) |
| Avg
low °F (°C) |
53 (11) |
54 (12) |
59 (15) |
64 (17) |
70 (21) |
74 (23) |
76 (24) |
76 (24) |
75 (23) |
68 (20) |
60 (15) |
54 (12) |
65 (18) |
| Rec
low °F (°C) |
25 (-3) |
30 (-1) |
32 (0) |
41 (5) |
55 (12) |
54 (12) |
67 (19) |
68 (20) |
61 (16) |
43 (6) |
29 (–1) |
20 (–6) |
20 (–6) |
|
Precipitation in. (mm) |
2.3 (58) |
2.8 (71) |
3.4 (86) |
1.6 (41) |
2.6 (66) |
5.7 (145) |
7.0 (178) |
7.8 (198) |
6.1 (155) |
2.5 (64) |
1.9 (48) |
2.2 (56) |
45.8 (1160) |
|
Source: Weatherbase |
See also
References
- Tampa Weather Forecasts on Yahoo! Weather.
Weather.yahoo.com. Retrieved on 2009-02-06.
- Keith C. Heidorn (2002). Weather Almanac for January 2002: Miami's First
Snowfall. The Weather Doctor. Retrieved on 2009-02-17.
- Jon Wilson (2007). The Great Tampa Bay snow of '89. St. Petersburg
Times. Retrieved on 2009-02-17.
- Tampa climate and weather, Florida, Rainfall Temperature
Climate and Weather. Wordtravels.com. Retrieved on
2009-02-06.
- http://www.tornadoproject.com/toptens/topten1.htm
- Jeff Klinkenberg (2008). Meet Thunderman. St. Petersburg Times.
Retrieved on 2009-02-06.
- St. Petersburg Times (1999). Lightning capital of the nation. Retrieved on
2009-02-06.
- Lightning Research Laboratory (UF).
Lightning.ece.ufl.edu. Retrieved on 2009-02-06.
- National Weather Service Office in
Tampa Bay, Florida (2009). Tampa Bay Area Tropical Weather Page. National Weather Service Southern
Region Headquarters. Retrieved on 2009-02-06.
- Craig Pittman (2009). Tampa Bay Water likely to overdraw from aquifer
this spring. St. Petersburg Times. Retrieved on
2009-02-06.
- Bob Macpherson (2008). Experts brief citizens on hurricane
preparedness. Tampa Bay Beach Beacon. Retrieved on
2009-02-17.
- Chris
Landsea (2005). Subject: E24) How long has it been since a hurricane or a
major hurricane hit a given community in the United States?
Hurricane Research Division.
Retrieved on 2009-02-06.
- Leonora Lapeter (2005). Hurricane season ends, yet lingers. St.
Petersburg Times. Retrieved on 2009-02-17.
- Jamie Thompson and Chase Squires (2004). 2004 Hurricane Season Ends. St. Petersburg
Times. Retrieved on 2009-02-17.
- Miles B. Lawrence and Hugh D. Cobb (2005). Tropical
Cyclone Report: Hurricane Jeanne 13 - 28 September 2004.
National Hurricane Center.
Retrieved on 2009-02-17.
- John L. Beven II (2004). Tropical Cyclone Report: Hurricane Frances 25 August - 8
September 2004. National Hurricane Center.
Retrieved on 2009-02-17.
- Richard J. Pasch, Daniel P. Brown, and Eric S. Blake (2005).
Tropical Cyclone Report: Hurricane Charley 9 - 14 August
2004. National Hurricane Center.
Retrieved on 2009-02-17.
- Stacey R. Stewart (2005). Tropical
Cyclone Report: Hurricane Ivan 2 - 24 September 2004.
National Hurricane Center.
Retrieved on 2009-02-17.