|New WFO Tallahassee Coastal Zones
The county warning area of WFO Tallahassee features one of the larger forecast areas along the Gulf Coast. This presents a series of challenges to forecasters when considering the effects of the Gulf of Mexico on weather patterns. Additionally, the threat of tropical cyclones and coastal flooding add complexity to the forecast. The impacts on the weather from the Gulf of Mexico extend year round. Whether these impacts occur with freeze forecasting in the winter, coastal flooding with spring storms, sea breeze convection in the summer, fire weather concerns in the spring and fall, or tropical cyclones during hurricane season, it is challenging to accurately delineate the impact of the Gulf within our forecast area.
The current zone configuration of NWS Tallahassee (Figure 1) is essentially based on the one county-one zone configuration. Only Walton County is separated into two zones. Local studies have clearly demonstrated the current zone configuration for coastal counties in the Tallahassee CWA does not allow forecasters to adequately take into account our improved understanding of local climatology when preparing forecasts, watches, and warnings for these coastal areas.
Figure 1. Current Tallahassee County Warning Area Zone Configuration
To improve forecast and warnings services for the region, The National Weather Service in Tallahassee will transition to new forecast zones for our Florida Coastal Counties on April 1, 2010. The initial impetus for modifying the Tallahassee CWA Zone configuration was to provide better service within the tropical program. One of our zones, Jefferson County, Florida, extends from the head of Apalachee Bay to the Georgia Border. As a result, when a tropical cyclone watch or warning is issued, this product appears to extend far inland. A similar scenario occurs when coastal flood watches or warnings are issued for this zone. To mitigate this issue, a proposal was presented to our local service enhancement team for consideration. This team provided additional guidance based on the following program areas:
1. Fire Weather Program: Improved fire weather forecasts and warnings are expected based on an improved ability to account for coastal effects. In any onshore winds regime, influence of the marain air mass will prevent critical fire weather conditions from occurring near the coast.
2. Temperature Forecasting: While influence on temperatures from the nearby Gulf occurs year round, this effect is most pronounces during the winter months. In many instances when temperatures drop into the upper 20s inland, freezing temperatures will not occur near the coast. Under the current zone configuration, this detail cannot be included in watches or warnings.
The map below shows the new Tallahassee County Warning Area Zone Configuration that will be implemented on April 1, 2010.
Figure 2. New Tallahassee County Warning Area Zone Configuration effective April 1, 2010.
These zone changes require new names be assigned to the new areas. These new zone names are explained in the chart below:
Other important information:
** These changes do not affect coding for NOAA Weather Radio in coastal counties. Thus, residents in these areas do not need to reprogram their weather radios to receive alerts.
If you have questions about the new zone changes within the Tallahassee forecast area, please contact Kelly Godsey at Kelly.Godsey@noaa.gov