A massive dust storm that formed over the Sahara Desert early this week has now pushed out over the tropical Atlantic, and will sharply reduce the odds of tropical storm formation during the first week of August. The dust is accompanied by a large amount of dry air, which is making the Saharan Air Layer (SAL) much drier than usual this week. June and July are the peak months for dust storms in the Southwest Sahara, and this week's dust storm is a typical one for this time of year.
JeffMasters, • 3:10 PM GMT on July 31, 2013
A weakening Tropical Depression Flossie passed through the Hawaiian islands on Monday evening and Tuesday morning with little fanfare, bringing scattered wind gusts of tropical storm force and a few areas of heavy rains of 1 - 2". The storm brought down a few trees and power lines, knocking out power for about 6,500 people on Maui and the Big Island. Kahului on Maui recorded sustained winds of 33 mph, gusting to 46 mph, at 7 pm local time Monday.
JeffMasters, • 3:25 PM GMT on July 30, 2013
A weakening Tropical Storm Flossie is closing in on Hawaii, where tropical storm warnings are flying for the entire island chain. Satellite images show that Flossie has lost most of its heavy thunderstorms, and continued weakening is expected as the storm traverses the islands, due to moderate wind shear and dry air aloft. Flossie's winds of 45 mph will likely drop to the 35 - 40 mph range as it passes through the islands on Monday afternoon and evening.
JeffMasters, • 3:40 PM GMT on July 29, 2013
Tropical Storm Flossie, a strong tropical storm with 65 mph winds, is headed west at 20 mph towards Hawaii. Satellite images show that Flossie is maintaining a modest area of heavy thunderstorms that are well-organized. The storm is over waters of 25°C, which is about 1°C below the water temperature typically needed to sustain a tropical storm. Flossie peaked in intensity Saturday morning, when the storm had 70 mph winds.
JeffMasters, • 3:15 PM GMT on July 28, 2013
Lee Grenci • 2:51 PM GMT on July 27, 2013
Lee Grenci • 3:54 PM GMT on July 26, 2013
Tropical Storm Dorian continues steaming west-northwest at 17 mph across the middle of the Atlantic Ocean with little change in appearance this morning. Satellite images show that Dorian is a small but well-organized system with a moderate amount of heavy thunderstorms.
JeffMasters, • 3:31 PM GMT on July 25, 2013
The season's fourth named storm, Tropical Storm Dorian, is here. Dorian formed unusually far east for so early in the season, at longitude 29.9°W. Only Hurricane Bertha of 2008, which became a tropical storm at 22.9°W longitude on July 3, formed farther to the east so early in the year.
JeffMasters, • 3:48 PM GMT on July 24, 2013
A strong and well-organized tropical wave that moved off the coast of Africa on Monday (98L) is located a few hundred miles south of the Cape Verde Islands and is moving west-northwest at 15 - 20 mph. Satellite images show that 98L has a decent amount of spin, but only a modest amount of heavy thunderstorms that have not changed much this morning.
JeffMasters, • 2:23 PM GMT on July 23, 2013
A strong and well-organized tropical wave moved off the coast of Africa on Monday, and has been designated 98L by NHC. This disturbance is headed west at 10 - 15 mph, and is under a moderate 10 - 15 knots of wind shear. A large amount of dry air lies to the north and west of 98L, and will likely interfere with development.
JeffMasters, • 3:38 PM GMT on July 22, 2013
According to the 2012 National Hurricane Center Forecast Verification Report, NHC should have drawn fewer yellow circles and more orange circles and red circles in their Tropical Weather Outlook during 2012, as there was a tendency to under-predict when a threat area might develop.
JeffMasters, • 2:46 PM GMT on July 20, 2013
June 2013 was the globe's 5th warmest June since records began in 1880, according to NOAA's National Climatic Data Center (NCDC). NASA rated it the 2nd warmest June on record. The year-to-date period of January - June has been the 7th warmest such period on record. June 2013 global land temperatures were the 3rd warmest on record, and global ocean temperatures were the 10th warmest on record.
JeffMasters, • 4:11 PM GMT on July 18, 2013
I learned something from watching the movie "Sharknado", SyFy Channel's twisted cross between Jaws, The Day After Tomorrow, and The Texas Chainsaw Massacre. My hurricane disaster kit is incomplete without a chainsaw. Not only can a chainsaw come in handy to remove fallen debris after the storm--it can be an essential self-defense weapon in case a hurricane spawns a "Sharknado"--a powerful waterspout that picks up man-eating sharks out of the ocean and hurls them miles inland.
JeffMasters, • 1:38 PM GMT on July 17, 2013
It was a very June for the contiguous U.S., ranking as the 13th wettest June since 1895. New Jersey and Delaware had their wettest June on record, and sixteen other eastern states had a top-ten wettest June. The very wet June has brought some of the highest soil moisture levels ever recorded for July along much of the coast from Florida to Maine, increasing the chances of extreme flooding should this region receive a hit from a tropical storm or hurricane.
JeffMasters, • 1:41 PM GMT on July 16, 2013
Over five thousand people missing in the wake of the devastating flooding that hit India's Himalayan Uttarakhand region on June 14 - 17, 2013, have now been declared dead, making the disaster India's deadliest monsoon flood event on record, and Earth's 4th deadliest weather-related disaster since 2000. The death toll of 5,748 tops India's previous record worst monsoon flood death toll of 4892, set in July 1968.
JeffMasters, • 3:10 PM GMT on July 15, 2013
A massive fire burning in northern Quebec is Canada's second largest fire since fire records began in 1959, according to the Canadian Forest Service. The fire was more than twice the size of Rhode Island on Tuesday--1,621,000 acres. Called the Eastmain fire, the near-record blaze was ignited by lightning on May 25, and was burning along a 100-km front near the east shore of James Bay by the village of Eastmain. At times, the fire spread at 19 mph (30 kph).
JeffMasters, • 2:14 PM GMT on July 13, 2013
The remains of Tropical Storm Chantal are bringing heavy rains and gusty winds to the Northwest Bahama Islands today, as the storm slides northwards at 10 mph. However, the storm is poorly organized with only a modest amount of heavy thunderstorm activity, and today's hurricane hunter mission into ex-Chantal has been cancelled. Before it dissipated on Wednesday, Chantal brought heavy rains to Haiti and the Dominican Republic. One drowning death in the Dominican Republic is being blamed on the storm.
JeffMasters, • 1:42 PM GMT on July 12, 2013
The remains of Tropical Storm Chantal are bringing heavy rains and gusty winds to the Southeast Bahamas and Turks and Caicos Islands today, after the storm dissipated on Wednesday approaching Haiti. Chantal brought heavy rains to Haiti and the Dominican Republic on Wednesday, with satellite estimates of 4 - 8 inches of rainfall in Central Haiti and the central and south coastal Dominican Republic. One drowning death in the Dominican Republic is being blamed on the storm.
JeffMasters, • 1:28 PM GMT on July 11, 2013
An Air Force hurricane hunter aircraft criss-crossing Tropical Storm Chantal this morning was barely able to find a closed circulation, and measured top winds of 45 mph at 10:10 am EDT in a region of heavy thunderstorms just south of the Central Dominican Republic coast. High wind shear of 20 - 30 knots, combined with dry air and the storm's exceptionally fast forward movement of 25 - 30 mph have seriously weakened Chantal, even before it has encountered the high mountains of Hispaniola and Cuba.
JeffMasters, • 3:24 PM GMT on July 10, 2013
Unusual Tropical Storm Chantal has strengthened a bit more as it speeds west-northwestwards at 29 mph away from the the Lesser Antilles Islands. Sustained winds of 38 mph, gusting to 52 mph, were observed at Martinique at 10 am AST as the storm passed. However, an automated weather station at the airport measured sustained winds of 60 mph, gusting to 78 mph, according to an official with Meteo-France. The Associated Press reported that Chantal ripped the roofs off of several homes on neighboring Dominica.
JeffMasters, • 8:06 PM GMT on July 09, 2013
Torrential rains from a series of "training" thunderstorms that moved over the same location brought Toronto, Canada its heaviest 1-day rainfall in recorded history on Monday, July 8. Toronto's Pearson Airport recorded 126 mm (4.96") of rain, beating Toronto's previous all-time rainiest day record set on October 15, 1954, during Hurricane Hazel, when 121.4 mm (4.78") fell. Weather records at the airport go back to 1937.
JeffMasters, • 4:20 PM GMT on July 09, 2013
Tropical Storm Chantal is strengthening as it speeds west-northwestwards at 26 mph through the Lesser Antilles Islands. At 6:22 am AST, St. Lucia recorded a wind gust of 54 mph. A 44 mph gust was recorded on Martinique at 9 am AST. An Air Force hurricane hunter aircraft is in the storm, and measured top winds at their 1,000' flight level of 80 mph at 8:41 am AST, about 20 miles north of the center. Top winds seen by the aircraft's SFMR instrument were about 60 mph.
JeffMasters, • 1:41 PM GMT on July 09, 2013
Tropical Storm Chantal is speeding westwards at 26 mph towards a Tuesday encounter with the Lesser Antilles Islands. Chantal has several well-developed low-level spiral bands that have gradually increased their heavy thunderstorm activity this morning. However, Chantal is fighting dry air associated with the Saharan Air Layer (SAL). The heavy thunderstorm activity near Chantal's center is rather thin, and there are virtually no heavy thunderstorms on the storm's north side.
JeffMasters, • 2:02 PM GMT on July 08, 2013
A strong and unusually well-organized tropical wave for so early in the season (95L) is speeding westwards at 20 - 25 mph, and will arrive in the Lesser Antilles Islands on Tuesday. 95L has a well-developed surface circulation center that is exposed to view, and the only factor keeping 95L from currently being classified as a tropical depression is the relative lack of persistent heavy thunderstorm activity near the center of the storm due to dry air.
JeffMasters, • 4:39 PM GMT on July 07, 2013
A tropical disturbance (94) is over the Western Gulf of Mexico, and is headed north towards the Texas/Louisiana coast at 5 - 10 mph. NHC gave the disturbance a 20% chance of developing into a tropical depression or tropical storm by Monday. As we approach mid-July, it's time to begin turning our attention to tropical waves coming off the coast of Africa. We have our first such system worthy of attention today, a tropical wave (95L) about 800 miles southwest of the Cape Verde Islands.
JeffMasters, • 1:53 PM GMT on July 06, 2013
A tropical disturbance over the Central Gulf of Mexico is headed northwest towards Texas at 5 - 10 mph. Satellite loops show a modest area of disorganized heavy thunderstorm activity associated with the disturbance, which is suffering from high wind shear of 20 - 30 knots due to strong upper-level winds from a trough of low pressure over the Western Gulf of Mexico. Dry air from the trough is also interfering with development.
JeffMasters, • 1:17 PM GMT on July 05, 2013
The jet steam is exhibiting unusual behavior over the U.S., a pattern we've seen become increasingly common in summertime over the past decade. There's a sharp trough of low pressure over the Central U.S., and equally sharp ridges of high pressure over the Western U.S. and East Coast. The ridge was responsible for more record-breaking heat on Tuesday. July 2. Most notably, Redding, California hit 116°, just 2° short of their all-time record.
JeffMasters, • 4:11 PM GMT on July 03, 2013
One of the greatest heat waves in North American history peaked on Sunday and Monday, but will still bring some of the hottest temperatures ever recorded to portions of the Western U.S. during the afternoon today. The extraordinary heat wave, caused by an unusually extreme standing wave pattern in the jet stream, brought Earth's highest June temperature ever recorded on Sunday, June 30, when the mercury hit 129.2°F in Death Valley, California.
JeffMasters, • 4:22 PM GMT on July 02, 2013