MIAMI-SOUTH FLORIDA National Weather Service Forecast Office

Transcription

1 MIAMI-SOUTH FLORIDA National Weather Service Forecast Office June 2015 South Florida Weather Summary Dry East, Wet West...Drought Remains SE Florida July 3, 2015: Depending on what side of the peninsula you are on, June was either typically wet and stormy or unusually dry and sunny. Rainfall for the month was decidedly skewed, with near to above normal rainfall over most of the western half of the peninsula and below normal rainfall over virtually all of southeastern Florida (Figures 1 and 2). Areas from western Collier County to western Glades County received over 10 inches of rain, while closer to Lake Okeechobee only 3 to 6 inches of rain was recorded. Across southeast Florida, rain amounts ranged from around 1 inch along the Atlantic beaches to near 6 inches over inland areas. The low rainfall amounts in southeast Florida came very close to establishing records for the month of June and resulted in the top 10 driest Junes on record at several locations (see table below). The primary cause of the wide variety in rainfall in June was a persistent subtropical high over the western Atlantic which extended across Florida (Figure 3). This persistent high pressure caused a prevailing east wind across south Florida, steering most of the afternoon thunderstorms towards the western half of the peninsula and Gulf coast. Meanwhile, east coast communities saw little of the night and morning showers typical of an easterly wind flow regime. The low rainfall amounts across southeast Florida, in combination with a dry May, have led to deteriorating drought conditions. As of June 30 th, severe drought conditions cover most of Miami-Dade and Broward counties, with moderate drought across most of Palm Beach County (Figure 4). Combined May/June rainfall also ranked among the top 10 driest such periods on record at several southeast Florida locations, including the following:

2 - Miami Beach: 2.30 (driest on record) - The Redland: 4.25 (3 rd driest) - Fort Lauderdale/Hollywood Int l: 3.06 (5 th driest) - Hialeah: 6.96 (6 th driest) - Miami International Airport: 5.99 (8 th driest) - Palm Beach International Airport: 5.58 (15 th driest) Here are June rainfall totals for select South Florida sites: Location (Beginning of Period of Record) June 2015 Rainfall (inches) Big Cypress 7.74 Brighton Reservation (Glades Co.) 5.15 Cape Florida 1.27 June Departure from Normal/Rank Canal Point (1941) Fort Lauderdale/Hollywood Int'l (1912) /2 nd driest Fort Lauderdale Dixie Water Plant Fort Lauderdale Beach 1.40 Hialeah (1940) /17 th driest Hollywood (1963) Homestead General Airport (1990) Immokalee (1971) Juno Beach 5.99 LaBelle (1929) Marco Island 2.74 Miami Beach (1928) /2 nd driest Miami International Airport (1911) /11 th driest Moore Haven (1918) /9 th driest Muse North Miami Beach 4.69 Naples East/Golden Gate 10.91

3 Naples Municipal Airport (1942) NWS Miami 3.54 Oasis Ranger Station (1979) Opa-Locka Airport 3.02 Ortona (1940) Palm Beach Gardens 3.77 Palm Beach International Airport (1888) Pembroke Pines North Perry Airport 0.88 Pompano Beach Airpark 2.07 Tamiami Airport West Kendall 4.13 The Redland (1942) /6 th driest South Bay (15S) 5.39 Figure 1: South Florida June rainfall.

4 Figure 2: South Florida June rainfall departure from normal. Figure 3: Mean 700 mb (approximately 10,000 ft) heights for June Orange and red colors indicate high pressure, with resulting east/southeast winds across southern Florida.

5 Severe Weather Impacts Figure 4: Drought Monitor for the end of June. Given that most of the rain fell across western parts of south Florida, it s not surprising that most of the strong wind gusts, hail and lightning reports also came from this general area. After a rather uneventful first few days of June, reports of strong wind gusts and small hail were across the greater Naples area from June 5 th through the 12 th. The impacts were mainly small trees uprooted and downed power lines. The exception to this pattern occurred on June 9 th and 10 th when strong storms temporarily shifted to eastern areas. A small, brief tornado touched down in Tequesta on the afternoon of June 10 th, with damage limited to trees uprooted/snapped and minor roof damage to a shopping center. After another relatively inactive period at mid-month, strong winds and lightning once again hit the Naples area. A wind gust of 56 mph was measured at Naples Municipal Airport on the afternoon of June 20 th, and lightning struck a home in the Aqualane Shores community of Naples, causing an estimated $2 million in damage. Storms shifted back to southeast Florida to end the month, with June 28 th being an active afternoon

6 across parts of metro Miami-Dade and Broward counties with several reports of tree damage and small hail. A wind gust of 63 mph was recorded in Davie on the afternoon of the 28 th. Temperature Warmest temperatures were observed in southeast Florida where less rainfall and cloud cover caused temperatures to be as much as 1.5 degrees above normal for the month. Much of this warmth was as a result of warm overnight/early morning low temperatures from east winds off the warm Atlantic. Conversely, temperatures were cooler along the Gulf coast due to the increased cloud cover and rainfall. The hottest part of south Florida, as typical, was the Everglades where temperatures hit the mid to upper 90s on many days, including 101 degrees at Oasis Ranger Station and 98 degrees in Muse on June 20 th. Miami International Airport recorded an average June temperature of 83.6 degrees Fahrenheit. This is 0.9 degrees above the 30-year normal for June and is the 7 th warmest June on record. The average high temperature was 90F, and average low temperature was 78F. The warmest reading of the month was 95 degrees on the 30 th (equaling a record high for the date). The coolest reading was 72 degrees on the 3 rd and 11th. High temperatures reached or exceeded 90 degrees on 16 days and low temperatures did not drop below 80 degrees on 10 days. Warmest minimum temperature records were tied or broken on 6 days. Fort Lauderdale/Hollywood International Airport recorded an average June temperature of 83.4 degrees Fahrenheit. This is 0.3 degrees above the 30-year normal for June and is the 7 th warmest June on record. The average high temperature was 89F, and average low temperature was 78F. The warmest reading of the month was 95 degrees on the 30 th. The coolest reading was 71 degrees on the 2 nd. High temperatures reached or exceeded 90 degrees on 13 days and low temperatures did not drop below 80 degrees on 14 days. Warmest minimum temperature records were tied or broken on 4 days. Palm Beach International Airport recorded an average June temperature of 82.7 degrees Fahrenheit. This is 1.3 degrees above the 30-year normal for June and is the 6 th warmest June on record. The average high temperature was 89F, and average low

7 temperature was 76F. The warmest reading of the month was 94 degrees on the 29 th. The coolest reading was 70 degrees on the 3 rd. High temperatures reached or exceeded 90 degrees on 16 days and low temperatures did not drop below 80 degrees on 8 days. Warmest minimum temperature records were tied or broken on 5 days. Naples Municipal Airport recorded an average June temperature of 81.8 degrees Fahrenheit. This is 0.1 degrees below the 30-year normal for June. The average high temperature was 90F, and average low temperature was 74F. The warmest reading of the month was 93 degrees on the 12 th and 30th. The coolest reading was 69 degrees on the 3 rd. High temperatures reached or exceeded 90 degrees on 21 days. Summer Temperature, Precipitation and Hazards Outlook The outlook by the NOAA Climate Prediction Center generally calls for a continuation of warmer and drier than normal conditions in July (Figures 5 and 6), with equal chances of wetter and drier than normal conditions through September. Therefore, little relief to the southeast Florida drought is expected through the end of July. Even in a relatively dry July, thunderstorms occur on a fairly regular basis, with lightning, gusty winds and localized flooding being the main impacts. Remember the basic lightning safety rule: when thunder roars, go indoors! The Atlantic hurricane season normally begins to get active in August and peaks in September and October. Although the latest NOAA seasonal outlook calls for a below normal number of tropical storms and hurricanes, south Florida can still be impacted by tropical systems in any year. Please use this time to get your hurricane plan ready and stock up on needed supplies. Also, rip currents are common throughout the summer and swimmers are strongly urged to swim near lifeguards and pay attention to the flags posted at Ocean Rescue lifeguard stands across South Florida. Visit the National Weather Service Rip Current Awareness page for more information. For the latest south Florida weather information, including the latest watches, advisories and warnings, please visit the National Weather Service Miami Forecast Office s web site at weather.gov/southflorida.

8 Figures 5/6: Climate Prediction Center Precipitation (top) and Temperature (bottom) outlooks for June-August.