|Forecasting Sea Fog in the Florida Panhandle
The Florida Panhandle has many forecasting challenges. The area experiences a wide range of severe
weather events ranging from severe thunderstorms to hurricanes. One of the other challenges facing
forecasters in the Florida Panhandle is the marine environment. Sea fog can be one of the most
challenging weather events caused by marine influences. Proper forecasting for sea fog requires
careful examination of temperatures, wind conditions and satellite images.
The AMS Glossary of Meteorology describes sea fog as "a type of advection fog formed when air that has
been lying over a warm water surface is transported over a colder water surface, resulting in cooling
of the lower layer of air below its dewpoint" (American Meteorology Society). Sea fog can cause
visibility problems for mariners, as well as motorists when it moves inland. Forecasters in the
Florida Panhandle area can expect sea fog to develop during the cooler months of October through
February. National Weather Service Meteorologist Kelly Godsey says this time of the year is a
common time for sea fog to form because this is "…when the sea surface temperature of the shelf
waters over the Gulf of Mexico cools significantly." When the dewpoint is close to the surface
water temperature, sea fog can form because "this will allow the parcel of air just above the
water's surface to cool to saturation, condense, and produce a fog droplet" (Godsey).
Forecasting for sea fog can be difficult because of less numerous coastal observation sites than those
found on land. An accurate forecast is crucial, especially to those who make a living through marine
jobs such as fishing. An inaccurate forecast of sea fog can be dangerous. If mariners are not aware
of the reduced visibility, it can prove fatal. Sea fog can also be tricky because it often moves
inland and affects motorists. It is difficult to predict exactly when the sea fog will move
inland. This is another factor that makes forecasting sea fog difficult.
For sea fog to form, the dewpoint of the shelf waters and the temperature of the air above the waters
can only vary by a couple of degrees. A moist airmass must enter the forecast area, and this could
come in the form of a warm front. However, the temperature combination must be one that will cause
saturation and condensation. As with any form of fog, windy conditions will inhibit its
development. Thus, calm conditions are the most favorable for sea fog formation. (Godsey)
When forecasting for sea fog, it is important to look at coastal observation sites. Not only will the
temperature need to be observed, but also the wind conditions. Meteorologist Jeff Haby points out on
theweatherprediction.com that fog forecasting can be tricky because it is often overlooked. Thus, one
of the best ways for a meteorologist to avoid the mistake of not forecasting sea fog is to be aware of
the time of year it is most likely and always be on the look-out for it. Once sea fog has formed, it
can be analyzed further by consulting satellite images. Meteorologists at the National Weather
Service Office in Tallahassee analyze sea fog at night by examining the IR channel of a satellite
or by using what is known as the fog product. The fog product "…examines the outgoing radiation
between 11 microns and 3.9 microns" (Godsey). This particular fog product may not be available
to all forecasters, such as those who work at television stations. When technology such as
this is not available, it can be particularly difficult to make an accurate sea fog forecast. In
situations such as this, forecasters must rely on products issued by the local National
Weather Service Office. Marine forecast discussions will usually contain information
about sea fog if it is occurring in the forecast area.
To learn more about sea fog formation, meteorologists can read journals from The American Meteorological
Society. There's also quite a bit of information about advection fog online. Caution should be taken
with the validity of all online resources unless it is from a credible source such as The American
Meteorological Society or The National Weather Service. Overall, the best way to learn about sea
fog and the effects it has on those living in marine areas is to have experience forecasting for
this weather event. Meteorologists who are new to an area should gather information from meteorologists
who have lived in the area for quite a while. First-hand observations also provide good insight
into the development of sea fog formation. It is not unheard of for television stations to
employ the help of weather watchers. These weather watchers may be mariners who call in to
the station and provide first-hand observations to the weather staff.
If a person has lived in a marine area, he or she will often notice that fog in the area can be
very thick. This is another reason sea fog is so dangerous. The Gulf of Mexico provides the moisture
needed for fog, and it also supplies condensation nuclei in the form of microscopic salt particles. It
is difficult to predict exactly when sea fog will lift. That's why it's a good idea to avoid stating
an exact time that the fog will lift (Haby). A close approximation will usually be the best route
for even an experienced forecaster. However, examination of temperature predictions on forecast
models and actual observations can help determine a time frame for the dissipation of the fog.
In conclusion, sea fog is a difficult event in which to forecast, and there is no easy solution. The best
way to improve forecasting accuracy of sea fog, as well as other weather events, is to practice. Forecasters
who have lived in an area for a while generally get familiar with weather patterns that influence
the area. Close examination of forecast models, surface charts and coastal observations can help
a forecaster recognize situations that are favorable for the formation of sea fog. Even though
local television meteorologists may not have access to advanced equipment such as the fog product
used by the National Weather Service Office in Tallahassee, they can rely on reports that
come from the NWS office, as well as first-hand reports from observers. Anyone forecasting
in the Florida Panhandle should always remember to check for sea fog, especially during
the fall and winter.
American Meteorological Society. "Sea Fog." AMS Glossary of Meteorology.
Allen Press. 6 April 2007
Godsey, Kelly. "Sea Fog Question." E-mail to the author. 4 April 2007.
Haby, Jeff. "Common Forecasting Mistakes." theweatherprediction.com. Meteorologist
Jeff Haby. 6 April 2007