Climatology



The terrain surrounding Pensacola is relatively flat, and does not stop the passage of transitory storms approaching from the west and southwest. The two major influences of terrain on weather in the Pensacola area are the Gulf of Mexico and the Mississipi River Valley. 

The Gulf of Mexico moderates weather in the local area, due to land-sea interactions. Tertiary land and sea breezes dominate the local area as far inland as 40 nm, depending on their intensity. The Gulf affects local area temperatures during the summer. Once the convective temperature (generally 10 degrees Fahrenheit (F) above the sea surface temperature) has been reached, the sea breeze dominates, and creates a nearly instantaneous 4-7 degree F drop in the air temperature.  In the winter, the Gulf moderates the Polar outbreaks and infrequent Arctic outbreaks along the coastal region.  In the near coastal regions, relatively warm water temperatures raise the minimum temperatures.  Minimum temperatures below freezing occur more frequently further inland (more than 10 nm). The Gulf does not stop the northeastward movement of  unstable waves that develop over southern Texas. Generally speaking, thunderstorms that form over the Gulf and move inland produce heavy precipitation and occasionally severe weather. 

The Mississippi River Valley extends from the Great Plains to the Gulf and provides a natural way for migratory pressure systems to enter the coastal regions. In the winter, frequent outbreaks of cP air (continental polar) and occasional cA air (continental arctic) reach the coastal area.  During the spring and fall, diffused and modified mP air masses are generally the rule. Frontal systems that affect the local area must have a deep upper-level trough that is large enough to to force the Polar Jet deep into the Four Corners region of the southwestern U.S. or central Texas. Freezing temperatures can be expected locally if this troughing is followed by a cA air mass. 

Forecasters reporting to Pensacola must have knowledge of both mid latitude and tropical meteorology. The local area is subject to subtropical and tropical systems. There are also severe thunderstorms and seasonal fog. However, Pensacola lies well south of the paths of the migratory storm systems that impact the U.S. north of 35 degrees N. 

Temperature
The average summer (June, July, and  August) temperature ranges from an average minimum of 74 degrees F. to an average maximum of 88 degree F. with an average of 81 degrees F. Temperatures of 90 degrees F or more occur on the average of 42 days per year. The average winter (December, January, and February) temperature ranges from an average miminum of 45 degrees F. to an average maximum of 62 degrees F. The daily average is 53 degrees F.  Temperatures at or below freezing occur on average of 17 days annually. The average dates of the first and last killing frosts are 9 December and 20 February. 

Bluffs
The bluffs located along the northwest section of Pensacola Bay supply a drainage wind. This drainage wind increases the gradient wind for 2-4 hours during the early mornings of spring and fall.

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