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Category: Tropical

Patricia Strongest Hurricane Ever in Western Hemisphere

| 11:37 am October 23, 2015

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Hurricane Patricia in the eastern Pacific underwent an incredible rapid intensification yesterday and overnight and aircraft reconnaissance found 175 knot winds (200 mph) just before 2 a.m. this morning. The central pressure was estimated at 880 millibars. I say estimated, because the dropsonde instrument used to record pressure, wind, temperature and other parameters did not splash down in the true center of the hurricane. The instrument recorded 885 mb and the crew estimated that the minimum pressure was 880 mb.

The winds make Patricia the strongest hurricane ever observed in the western hemisphere. Patricia is stronger than Wilma from 2005, which had the distinction of having the lowest central pressure observed in the Atlantic (882 millibars). And the top winds of 175 knots are certainly the strongest observed in any tropical cyclone around the world since 1970. Wind speeds were probably routinely overestimated prior to 1970. Patricia is stronger than Haiyan, which has 170 mph winds in the northwestern Pacific and Allen, which had 165 knot winds in 1980 in the North Atlantic.

Typhoon Tip still holds the distinction of having the minimum central pressure observed around the globe, with 870 millibars measured by reconnaissance on October 12, 1979. But Tip’s winds were 165 knots, short of Patricia’s record this morning.

Water temperatures underneath Patricia are running 30C, which is about 1 degree C warmer than they have been ever observed in the past 34 years. Cloud tops around the center have warmed a bit in the past couple of hours, perhaps indicating some weakening, but catastrophic conditions will occur along the coast near and east of where the center makes landfall. Fortunately, there are no major population centers in the swath where the maximum effects are expected to occur.

Landfall will come early this evening on the Mexican coast west of Manzanillo in the state of Jalisco. This is southeast of Puerto Vallarta, where they will experience tropical storm force winds in just a couple of hours and strong tropical force winds by 7-8 p.m. tonight. Hurricane conditions may remain just east of Puerto Vallarta.

It will turn to the north northeast over the mountainous terrain of Mexico. It should weaken to tropical storm force by tomorrow afternoon and become a remnant low by Sunday. It will bring torrential rains to Mexico and South Texas even as it weakens. The remnant low will get revitalize over Coastal Texas over the weekend and could bring heavy rain to southern and eastern Texas, as well as southern Louisiana. The WPC is calling for widespread 3-8 inch amounts from the eastern half of Texas all the way into Arkansas and western Mississippi and western Tennessee.

As the low moves slowly northeast, it may bring a nice rain event to Alabama by next Tuesday with an inch of rain possible.

Joaquin Passing NW of Bermuda

| 8:10 pm October 4, 2015

It’s been a cloudy, rainy, and rather blustery day for the people in Bermuda. Hurricane Joaquin, though diminishing some in strength, has been traveling northward just to the west of Bermuda. It appears from the Bermuda Weather Service radar that the center of Joaquin passed just west of the island nation with the eastern edge of the eye wall only 80 kilometers west of the radar site. The latest radar image is shown below and indicated that Joaquin was west-northwest of the island and moving away.


According to weather observations taken at the L. F. Wade International Airport, the highest sustained wind was from the south at 46 mph with a gust to 64 mph. The barometric pressure was reported to be at 29.25 inches which is the lowest value reported so far today.

I’m afraid all this interest in the hurricane focused on Bermuda has piqued my travel interests to visit that island – after they recover.


Radar View of Joaquin

| 3:16 pm October 4, 2015

While we are mostly interested in the weather in Central Alabama, it’s always interesting to peek in on other places that are having weather. And let’s be honest, our interest is usually piqued when the weather in those other locations is bad. So today there is a lot of interest in South Carolina with their epic flooding and in Bermuda as Hurricane Joaquin slips by the island just to the west.

So I thought blog viewers might be interested in the radar view of Joaquin from the Doppler radar located at the L.F.Wade International Airport in Bermuda. The radar is an S-Band Meteor 1500S built by AMS Gematronik purchased by the Department of Airport Operation and is operated by the Bermuda Weather Service.

Bermuda radar view of Joaquin

As you might imagine, the weather in Bermuda is horrible. This afternoon, about 90 minutes ago, they reported an ESE wind at 39 mph gusting to 51 mph. Highest gust this afternoon has been 55 mph. The pressure has been falling all afternoon as Joaquin traverses the ocean just west of Bermuda and the latest report was 29.36 inches or 994 millibars.

Looking at the radar image, it appears Joaquin should be due west of Bermuda in about 2 to 3 hours with the eastern most eye wall about 80 km from the radar site.


PS I updated this to include a satellite image of Joaquin with Bermuda marked on the map (small black mark just east of Joaquin) for some perspective.

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A Look at Rain in SC

| 8:44 am October 3, 2015

I know that South Carolina is a long way off, but weather enthusiasts are focused on that area because of what is likely to become a rain event of historic proportion. The National Weather Service Forecast Office in Greenville/Spartanburg working with other NWS offices in Columbia, Charleston, and Wilmington, prepared the graphic below. This graphic is based on actual rainfall reports and showed a rather large swath of 3 to 6 inch amounts over the eastern half of South Carolina. Unfortunately, the rain is going to keep on going much like that persistent pink bunny that represents Energizer batteries.



Joaquin Is Pegging the East Coast Excitement Meter

| 12:15 pm September 30, 2015

Well, the excitement meter has shot up rapidly last night and this morning on Joaquin.

The storm became a hurricane this morning with winds of 80 mph and it continues to strengthen. Air Force reconnaissance found a central pressure of 972 mb after 7 a.m. You can see it tracking southwestward perilously close to the Bahamas with the hurricane watches and warnings outlined in peach and red.

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The system is developing an eye now and will continue to strengthen over warm water. Sea surface temperatures in the vicinity of the hurricane are well over 30C, which is sufficient for rapid strengthening.

It is quite impressive on visible satellite imagery, with intense thunderstorms wrapping around the developing eye and good outflow. Joaquin is expected to become a major hurricane over the next 48 hours. Indeed, with very low wind shear and the warm temperatures, it is not unthinkable that it could become even stronger.

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Hurricane Joaquin is 300 miles east southwest of Nassau in the Bahamas, moving SW at 5 mph. It is expected to turn sharply west, then northwest and then north and northeast over the next 24 hours. It will bring tropical storm conditions to the southern Bahamas tonight and Thursday, and hurricane conditions to San Salvador. Hurricane warnings are in effect for the southern Bahamas. A hurricane watch is in effect for the rest of the Bahamas including Nassau, but I think that is out of a measure of caution, since only the island of Eleuthera should receive tropical storm conditions late Thursday night into Friday morning.

With the northeast turn, you would think it would turn on out to sea and bother no one. But not so fast my friend. Strengthening high pressure to the north of the hurricane may very well deflect it back to the west by the weekend and Joaquin poses a big threat to the U.S. East Coast. (Think Hurricane Sandy from 2012.)

The GFS and the Canadian, as well as the GFDL and HWRF models have been bullish on a solution that takes Joaquin into the Mid-Atlantic Coast between eastern North Carolina and the Delaware/Maryland/Virginia area (DELMARVA). The European model still takes it out to sea without affecting land. But the ensembles (multiple runs of the model with slightly different data to generate a variety of solutions) underscore the uncertainty. The GFS ensemble has members that carry it out to sea with others that bring it ashore. The positions from the various members of the European ensemble actually average out to be closer to the coast as well. The Canadian overnight was right with the American GFS.

So, there has been an increasing trend toward a landfall on the U.S. East Coast in the Mid-Atlantic region. The morning run of the GFS model now shows a landfall near Morehead City, NC Saturday night.


The overnight run of the GFDL pegged Virginia Beach as the landfall Saturday night as a 115 mph hurricane with a central pressure of 943 mb. That would be a disaster for the Hamptons and the Chesapeake Bay including Washington DC and Baltimore. The HWRF brings it to near Cape Hatteras as a 100 mph hurricane early Sunday morning and on into southern Virginia.

It is too early to say specifically where Joaquin will end up, but all interests along the East Coast of the United States from the Carolinas to New England need to be paying attention to the latest forecasts, official advisories and watches and warnings.

Heavy rains will continue to plague the area from the Carolinas to New England. Flood watches are in effect for a large area of this region. Much of the Mid-Atlantic region is forecast to get 8-10 inches of rain from this storm. Serious flooding was reported this morning in Portland ME.

Coastal flood advisories are in effect along much of the East Coast from the Florida Keys to Massachusetts. High astronomical tides caused flooding around Charleston SC this morning, closing some streets.

We will be tracking Joaquin carefully here on the blog through the weekend as it decides what it is going to do.

Increasing Rain Chances; Update on Gulf Low

| 2:24 pm September 27, 2015


Moisture levels are high across Alabama on this late September Sunday afternoon. Clouds are thick across the area and light showers are increasing across the Central part of the state.

Temperatures are edging toward the 80F mark, but many spots will hang in the 70s this afternoon. Skies will remain mostly cloudy and scattered showers will be possible.

Expect the rain to expand this evening and most spots will see 30-45 minutes of rain late between this afternoon and tonight. Rainfall amounts will be light, around one tenth of an inch.

SUPERMOON ECLIPSE: I am afraid the only way that you will see the big lunar event tonight is by traveling far away or watching it on The moon will be eclipsed by the Earth’s shadow this evening in a total eclipse, even as the Moon is at perigee, its closest point in its orbit around the Earth. All for naught I am afraid for us here in Alabama.

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TROPICAL LOW? A broad low is over the Yucatan early this afternoon, with lots of disturbed weather extending northward from the system all the way into the coastal waters of the Florida Big Bend from Apalachicola to Tampa. More storms are over the Texas and Louisiana coastal waters, associated with the upper level low. I think we are seeing better outflow this morning from the storms each of the Yucatan where ridge is building.

The National Hurricane Center has dropped their probability that this low might become a tropical cyclone to 30%. Wind shear has relaxed a bit in the region where the low is situated now, but it still about 20 knots, which makes conditions unfavorable for significant development. And to the northwest, there is over 40 knots of shear. Even if it doesn’t become a tropical depression, with will have significant impact along the Gulf Coast, with heavy rain, winds of around 40 mph, seas of 6-8 feet and a high rip tide threat until the low comes ashore Tuesday. We will look at the beach forecast shortly.

WET START TO THE WORK WEEK: As the low moves northward on Monday, waves of showers will spread northward. Monday won’t be an all day rain by any stretch, but should will have to dodge at least a couple of rounds of rain. The low should reach the coast Monday night or early Tuesday. Showers will be the rule again on Tuesday as the low turns northeastward. They will begin to diminish from the south Tuesday afternoon, but they won’t be done. &0s will be the rule Monday and Tuesday with the clouds and showers.

MIDWEEK MOISTURE: The leftover moisture will hang around into midweek. Meanwhile, a developing trough to the north will link with the upper low over Louisiana, forming a bigger trough and pushing a cold front our way. There should be one last hurrah of showers and storms Wednesday afternoon as the front pushes through, and then the front.

BUT THEN, WAIT: We had thought there would be improved weather for the remainder of the week into the weekend, but the GFS has introduced the idea that an upper level low may cut off in the deep trough that is left over the Ohio and Tennessee Valleys. If that happens, we probably will see enough atmospheric energy and moisture to trigger a few showers Thursday. Expect improving conditions as we head toward the weekend.

ROCKET CITY WEATHER FEST: Speaking of the weekend, the annual Rocket City Weather Fest is this coming weekend at UAH in Huntsville. Lots of fun activities for kids and education things for everyone. There will even be a weather balloon launch at 1 p.m. Check out their website.

TD Nine Forms

| 10:56 am September 16, 2015

Tropical Depression Nine has formed in the middle of the south Atlantic. As we’ve been telling you, the depression is no threat to land, only to shipping in the middle Atlantic. I’ve pasted the public advisory into this post below. The forecast graphic is below the advisory, so you’l need to scroll down to see it.


WTNT34 KNHC 161433

1100 AM AST WED SEP 16 2015


LOCATION...15.0N 43.1W

There are no coastal watches or warnings in effect.

At 1100 AM AST (1500 UTC), the center of Tropical Depression Nine
was located near latitude 15.0 North, longitude 43.1 West. The
depression is moving toward the north-northwest near 8 mph (13 km/h)
and this motion is expected to continue through Thursday. A turn
toward the northwest is forecast on Thursday night.

Maximum sustained winds are near 30 mph (45 km/h) with higher gusts.
Little change in strength is forecast during the next 48 hours.

The estimated minimum central pressure is 1010 mb (29.83 inches).


Next complete advisory at 500 PM AST.
TD 9 Forecast Graphic

TD 9 Forecast Graphic

55th Anniversary, Hurricane Donna

| 7:34 am September 11, 2015

It was 55 years ago that an impressionable young man in the 6th grade experienced the fury of Hurricane Donna. His interest was further heightened through the presentation of the storm by one of the Nation’s first on-air degreed meteorologists, Roy Leep. It was this encounter which set him firmly on the road to a career in meteorology. And today the Hurricane Research Division of NOAA’s Atlantic Oceanographic and Meteorological Laboratory in Miami has put together a great page documenting Donna. You can find that page by clicking on this link.

Below is a map of the Atlantic Basin showing the complete path of Hurricane Donna as well as the paths of the other six tropical storms for 1960.


1960 Tropical Storm Tracks

Peeking in on Grace

| 1:49 pm September 6, 2015

I was looking through some images of Grace, and I thought people might like to see a couple of different views of this storm. These two images were taken about 15 minutes apart just before 1 pm CDT.

The first one below comes from the eastern GOES satellite operated by the NOAA Satellite and Information Service. This is a visible image, so this is what it would look like if we were on the satellite looking down with special black and white glasses. Grace is showing some good banding on the south and east sides of the storm but is pretty open in the northwest quadrant.


Looking more westerly is a visible image from the European Meteorological Satellite. Fred can be seen in the upper left quadrant of the image.


I just can’t imagine life without weather satellites.


TD 7 Becomes Grace

| 3:57 pm September 5, 2015

It really did not take long for tropical depression 7 to move up the ladder to a full fledged tropical storm dubbed Grace.


NHC forecasters are keeping their official track on the south side of the overall envelope of the various computer guidance tracks. Synoptic conditions should be conducive for some intensification during the next 24 to 36 hours, with the storm embedded in an environment of light easterly shear and over warm SSTs. The one caveat is that a general drying of the lower to middle troposphere
in the near-storm environment is forecast, possibly due to increasing subsidence, which could squelch additional strengthening. After 48 hours, the cyclone is expected to encounter westerly flow aloft associated with an enhanced upper-level trough extending from near the Antilles to the eastern tropical Atlantic. This pattern should produce enough vertical shear to cause weakening or possibly
even dissipation by day 4 or 5 of the forecast as it nears the Lesser Antilles.