Post on 07-Aug-2020
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Current Watches and Warnings A Hurricane Warning is in effect from Fernandina Beach southward around the Florida peninsula to the Indian Pass; Florida Keys; Lake Okeechobee; Florida Bay; Cuban provinces of Ciego de Avila, Sancti Spiritus, Villa Clara, Matanzas, and Havana; Andros Island, Bimini and Grand Bahama
A Hurricane Watch is in effect from north of Fernandina Beach to Edisto Beach
A Tropical Storm Warning is in effect for west of Indian Pass to the Okaloosa/Walton County line
A Storm Surge Warning is in effect from South Santee River southward to Jupiter Inlet; North Miami Beach southward around the Florida Peninsula to the Ochlockonee River; Florida Keys; Tampa Bay
Current Details from the National Hurricane Center (NHC)
COORDINATES: 25.0° north, 81.5° west LOCATION: 80 miles (125 kilometers) south-southeast of Naples, Florida MOVEMENT: north at 9 mph (15 kph) WINDS: 130 mph (210 kph) with gusts to 160 mph (260 kph) RADIUS OF TROPICAL STORM-FORCE WINDS: 220 miles (350 kilometers) RADIUS OF HURRICANE-FORCE WINDS: 80 miles (130 kilometers) MINIMUM CENTRAL PRESSURE: 933 millibars SAFFIR-SIMPSON SCALE RANKING*: Category 4 Hurricane 1st LANDFALL LOCATION: Cudjoe Key (Florida Keys) 1st LANDFALL TIMEFRAME: approximately 9:10 AM local time (13:10 UTC) 1st LANDFALL INTENSITY: 130 mph (210 kph) – Category 4 Hurricane 24-HOUR LANDFALL POTENTIAL: HIGH (Florida West Coast) 24-HOUR SIGNIFICANT INSURED LOSS POTENTIAL: HIGH
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Cat Alert: Hurricane Irma 2
Latest Satellite Picture
Source: NOAA
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Cat Alert: Hurricane Irma 3
Discussion Hurricane Irma, located approximately 80 miles (125 kilometers) south-southeast of Naples, Florida, is currently tracking north at 9 mph (15 kph). Latest observations from the Air Force Hurricane Hunters had flight-level winds that corresponded to surface winds justifying the NHC maintaining Irma’s intensity at 130 mph (210 kph) – a Category 4 storm. Irma should maintain this intensity until the center reaches the southwest Florida coast, and then begin to weaken while the system interacts with the landmass of the Florida peninsula. Increasing southwesterly shear associated with an upper-level frontal boundary should also cause weakening of the hurricane during the next day or so. More rapid weakening is likely after Irma moves into the southeastern United States within the next 24 to 36 hours, and the cyclone should weaken to a remnant low in 72 hours (or sooner). The official NHC intensity forecast is close to the forecast model consensus.
The center of Irma wobbled more northward over the past few hours. Irma is embedded within a broad mid-level gyre over the Gulf of Mexico. The cyclone is expected to be steered north-northwestward at a faster forward speed over the next day or two on the eastern side of the gyre. This will take Irma inland over northern Florida early on Monday and the southeastern United States over the next couple of days. The model track guidance remains fairly tightly clustered, with the ECMWF (Euro) track a little to the left and slower than the other models. The official NHC track forecast lies between the model consensus and the ECMWF solution. This is just slightly east of the previous official forecast.
Key Messages from the National Hurricane Center
1. Life-threatening wind and storm surge from Irma will continue in the Florida Keys and southwestern Florida today and spread into central and northwestern Florida tonight and Monday. Preparations in central and northwestern Florida should be rushed to completion.
2. There is imminent danger of life-threatening storm surge flooding along much of the Florida west coast, including the Florida Keys, where a Storm Surge Warning is in effect. The threat of catastrophic storm surge flooding is highest along the southwest coast of Florida, where 10 to 15 feet of inundation above ground level is expected. This is a life-threatening situation.
3. Irma will bring life-threatening wind impacts to much of Florida regardless of the exact track of the center. Wind hazards from Irma are also expected to spread northward through Georgia and into portions of Alabama, Tennessee, South Carolina, and North Carolina.
4. Irma is expected to produce very heavy rain and inland flooding across much of Florida and many other parts of the southeast United States. Rainfall occurring very quickly, at 2 to 4 inches per hour, will lead to flash flooding and rapid rises on creeks, streams, and rivers. Significant river flooding is likely over the next five days in the Florida peninsula and southeast Georgia, where average rainfall of 8 to 15 inches and isolated 20 inch amounts are expected. Significant river flooding is also possible beginning Monday and Tuesday in much of eastern and central Georgia, western South Carolina, and western North Carolina, where average rainfall of 3 to 8 inches and isolated 12 inch amounts are expected. Mountainous parts of these states will be especially vulnerable to flash flooding. Farther west, Irma is expected to produce average amounts of 2 to 5 inches in parts of Alabama and Tennessee, where isolated higher amounts and local flooding may occur.
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Cat Alert: Hurricane Irma 4
Additional Information
STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water is expected to reach the following HEIGHTS ABOVE GROUND if the peak surge occurs at the time of high tide:
Cape Sable to Captiva: 10 to 15 feet Captiva to Ana Maria Island: 6 to 10 feet Card Sound Bridge through Cape Sable, including the Florida Keys: 5 to 10 feet Ana Maria Island to Clearwater Beach, including Tampa Bay: 5 to 8 feet North Miami Beach to Card Sound Bridge, including Biscayne Bay: 3 to 5 feet South Santee River to Fernandina Beach: 4 to 6 feet Clearwater Beach to Ochlockonee River: 4 to 6 feet Fernandina Beach to Jupiter Inlet: 2 to 4 feet North of North Miami Beach to Jupiter Inlet: 1 to 2 feet
The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large and destructive waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.
The combination of a life-threatening storm surge and large breaking waves will raise water levels ABOVE NORMAL TIDE LEVELS by the following amounts within the hurricane warning area near and to the north of the center of Irma. Near the coast, the surge will be accompanied by large and destructive waves.
Water levels along the north coast of Cuba will gradually subside today.
WIND: Hurricane conditions are expected to continue within the Hurricane Warning area along the north coast of Cuba through this morning. Hurricane conditions are continuing across portions of the Florida Keys and southern Florida. Winds affecting the upper floors of high-rise buildings will be significantly stronger than those near ground level. Tropical storm and hurricane conditions are expected to spread northward across the remainder of the warning areas through Monday. Tropical storm conditions are possible in the watch area in the Northwestern Bahamas today.
RAINFALL: Irma is expected to produce the following rain accumulations through Wednesday:
Western Cuba: additional 1 to 3 inches (isolated 5 inches) Western Bahamas: additional 2 to 4 inches (isolated 6 inches) The Florida Keys: 15 to 20 inches (isolated 25 inches) Western Florida peninsula: 10 to 15 inches (isolated 20 inches) Eastern Florida peninsula and southeast Georgia: 8 to 12 inches (isolated 16 inches) The rest of Georgia, the eastern Florida Panhandle, southern & western South Carolina, and western North Carolina: 3 to 8 inches (isolated 12 inches) Eastern Alabama and southern Tennessee: 2 to 5 inches
In all areas this rainfall may cause life-threatening flash floods and, in some areas, mudslides.
TORNADOES: Tornadoes are possible through tonight, mainly across southern, central, and eastern portions of the Florida Peninsula.
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Cat Alert: Hurricane Irma 5
THE EYE: Do not venture outside when the calm eye of the hurricane passes over, as dangerous winds will return very quickly when the eye moves away.
SURF: Swells generated by Irma are affecting the southeast coast of the United States. These swells are likely to cause life-threatening surf and rip current conditions.
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Cat Alert: Hurricane Irma 6
National Hurricane Center Forecast
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Cat Alert: Hurricane Irma 7
Most Likely Arrival Time of Tropical Storm-Force Winds
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Cat Alert: Hurricane Irma 8
National Hurricane Center: Wind Speed Probabilities
Tropical Storm-Force Wind Probabilities (≥40 mph (65 kph))
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Cat Alert: Hurricane Irma 9
Wind Probabilities (≥60 mph (95 kph))
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Cat Alert: Hurricane Irma 10
Hurricane-Force Wind Probabilities (≥75 mph (120 kph))
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Cat Alert: Hurricane Irma 11
NHC: Storm Surge Watch/Warning Graphic
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Cat Alert: Hurricane Irma 12
NHC: Storm Surge Inundation Graphic
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Cat Alert: Hurricane Irma 13
Weather Prediction Center: Rainfall Potential
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Cat Alert: Hurricane Irma 14
Current ‘Spaghetti’ Model Output Data
Source: NHC
Additional Information and Update Schedule Wind intensity forecasts and forecast track information can be found via the National Hurricane Center at www.nhc.noaa.gov NEXT CAT ALERT: Sunday afternoon after 4:00 PM Central Time (21:00 UTC).
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Cat Alert: Hurricane Irma 15
*Tropical Cyclone Intensity Classifications for Global Basins WIND SPEED BASINS AND MONITORING BUREAU
KTS1 MPH1 KPH1
NE Pacific, Atlantic
NW Pacific
NW Pacific
SW Pacific Australia SW
Indian North Indian
National Hurricane
Center (NHC)
Joint Typhoon Warning
Center (JTWC)
Japan Meteorological Agency (JMA)
Fiji Meteorological Service (FMS)
Bureau Of Meteorology
(BOM) Meteo-France
(MF)
India Meteorological
Department (IMD)
30 35 55 Tropical Depression
Tropical Depression
Tropical Depression
Tropical Depression
Tropical Low
Tropical Depression
Deep Depression
35 40 65
Tropical Storm
Tropical Storm
Tropical Storm
Cat. 1 Tropical Cyclone
Cat. 1 Tropical Cyclone
Moderate Tropical Storm
Cyclonic Storm 40 45 75
45 50 85
50 60 95 Severe Tropical Storm
Cat. 2 Tropical Cyclone
Cat. 2 Tropical Cyclone
Severe Tropical Storm
Severe Cyclonic Storm
55 65 100
60 70 110
65 75 120
Cat. 1 Hurricane
Typhoon
Typhoon
Cat. 3 Severe Tropical Cyclone
Cat. 3 Severe Tropical Cyclone
Tropical Cyclone
Very Severe
Cyclonic Storm
70 80 130
75 85 140
80 90 150
85 100 160
Cat. 2 Hurricane 90 105 170
Cat. 4 Severe Tropical Cyclone
Cat. 4 Severe Tropical Cyclone Intense
Tropical Cyclone
95 110 175
100 115 185
Cat. 3 Major
Hurricane
105 120 195
110 125 205
Cat. 5 Severe Tropical Cyclone
Cat. 5 Severe Tropical Cyclone
115 130 210
120 140 220
Cat. 4 Major
Hurricane Very Intense Tropical Cyclone
Super Cyclonic Storm
125 145 230
130 150 240
Super Typhoon
135 155 250
140 160 260 Cat. 5 Major
Hurricane >140 >160 >260
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Cat Alert: Hurricane Irma 16
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