Florida Climate Center

Prepared by Daniel J. Brouillette
Florida Climate Center
The Florida State University
Tallahassee, FL

Mean temperatures in August were mainly near to slightly above normal across the state, except in a portion of the north-central part of the peninsula, where they were considerably above normal. The anomalies in monthly mean temperature were mix of positive and negative across the state but near to slightly above normal, overall, ranging from as positive as +2.6˚F at Gainesville and Melbourne in the north-central part of the state to as negative as -0.7˚F at Fort Myers and Miami in the coastal southern sections (Table 1 and Appendix 1).  Continuing a long-term trend, anomalies in monthly mean minimum temperature were more positive than anomalies in monthly mean maximum temperatures.  August 2018 was the second warmest at Melbourne, sixth warmest at Gainesville, and seventh warmest at Orlando.  Several high temperature records and one low temperature record were tied or broken across the state (Appendix 2). 

Table 1. August average temperatures and departures from normal (˚F) for selected cities.

Rainfall totals in August were much above normal over most of the panhandle, near to above normal in the western one-third of the peninsula, and below normal in many areas of the eastern peninsula and Keys, with considerable local variability characteristic of the summer months in Florida (Figure 1).  Station anomalies ranged from -5.51” at Melbourne to +6.83” at Tampa (Table 2 and Appendix 1) (Figure 1). A few 24-hour precipitation records broken for the month (Table 3).

Table 2. August precipitation totals and departures from normal (inches) for selected cities.

Table 3. Select daily rainfall records (inches) broken during August. (Compiled from NOAA, NWS)

Figure 1. A graphical depiction of the monthly rainfall departure from normal (inches) for May is given in the figure below (courtesy of NOAA, NWS). 

ENSO-neutral conditions are present in the Pacific, with El Niño favored to develop.

Based on current data and forecast models, forecasters with the Climate Prediction Center (CPC) have issued an El Niño Watch.  ENSO-neutral conditions currently are present, with sea-surface temperatures (SST) near to above average across the equatorial Pacific Ocean. The chance of El Niño development during the climatological boreal autumn (from now through the end of November) is rated at near 60% and near 70% during the climatological boreal winter (December-January-February).  The CPC seasonal outlook favors above-normal temperatures and above-normal precipitation through September 2018.  For the climatological autumn as a whole (through the end of November), there is equal probability of below-, near-, and above-normal temperatures and above-normal rainfall in Florida.

Hazardous Weather Events in August.

According the Local Storm Reports (LSRs) issued by the local National Weather Service (NWS) offices serving Florida, 208 instances of hazardous weather were reported across the state in August 2018. 

Table 4. Breakdown of storm reports submitted in Florida during the month of August. (Compiled from Iowa State University/Iowa Environmental Mesonet.)

Drought-Related Impacts

At the end of August, according to the U.S. Drought Monitor, all of Florida was drought free, continuing conditions that have been present since the late spring.  Western Escambia County, accounting for 0.26% of the state’s land area, had abnormally dry conditions in the second half of the month, owing to rainfall deficits over the last 30 to 60 days. 

As of 5 September, the Lake Okeechobee water level was at 14.65 ft. above sea level, which is above average for this time of the year.

Agriculture-Related Impacts.

At the beginning of September, topsoil-moisture levels were at mainly adequate although about one-quarter of the state had surplus topsoil-moisture levels, mainly on the panhandle, and about two percent was short on topsoil moisture.

A major theme through the month has been the continuation of very wet soil conditions on the panhandle, which has hindered the cutting of hay and the harvest of peanuts at times.  Flooded low-lying areas in the St. Johns River valley negatively impacted cattle pasture lands.  Summer crops, including avocado, bitter melon, boniato, malanga, mango, and okra, were harvested; good conditions generally persisted for citrus, allowing spray schedules to be followed and grove maintenance performed.  The preparation of land for fall vegetable cultivation was managed as conditions allowed and planting started. 

Appendix 1
Additional May Departures from Normal Data for Florida Locations

Appendix 2
Select daily maximum and minimum temperature records (^oF) tied or broken during May.
(Compiled from NOAA, NWS)

*This value ties the all-time highest minimum temperature ever recorded at Melbourne (records back to 1937), last set on 14 July 2017.