Monday, July 05, 2010

July Tropical Climatology

 

 


# 4697

 

 

Most years, July isn’t a big month for Hurricanes in the Atlantic and Caribbean, although in 2005 we saw 3 storms (Cindy, Dennis, Emily) develop in the first half of that month.  

 

Normally, things don’t start to get active until mid-August.  

 

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But this year, the forecast is for a very active season, and so it isn’t too early to be paying attention.  Alex, which went into Northern Mexico last week, was the strongest June Hurricane in more than 50 years.

 


For those along the Gulf and Atlantic coasts – including the Deepwater Horizon cleanup crews – the latest tropical weather outlook from the NHC will be of interest. 

 

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The National Hurricane Center in Miami is watching 4 areas of suspicion.

 

While three of these areas (yellow circles) currently have low probability of intensification over the next 48 hours, one area south of the Cayman Islands (red circle) shows promise (50%). 

 

This is roughly the same area where Alex formed a little more than a week ago.

 

The July 5th 2am Tropical Weather Outlook states:

 

THE TROPICAL DISTURBANCE LOCATED OVER THE NORTHWESTERN CARIBBEAN SEA HAS CHANGED LITTLE OVER THE LAST SEVERAL HOURS...AND THERE ARE NO SIGNS OF A SURFACE CIRCULATION. HOWEVER... ENVIRONMENTAL CONDITIONS ARE FAVORABLE FOR ADDITIONAL DEVELOPMENT... AND A TROPICAL DEPRESSION COULD FORM OVER THE NEXT COUPLE OF DAYS AS THIS SYSTEM MOVES WEST-NORTHWESTWARD OR NORTHWESTWARD AT 10 TO 15 MPH.  THERE IS A MEDIUM CHANCE...50 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. . . .

 


In other words . . . nothing yet, but conditions there are conducive to development . . . so we should keep an eye on it.

 

Early models suggest this system may move into the Gulf of Mexico later in the week.  Until a system has developed with a well defined center of circulation, however, these models tend to be of limited value.

 

Even then, these models can widely vary in forecast track.  While interesting to watch, the safest bet is to base your plans on the NHC forecasts.

 

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Climatologically speaking, these areas of suspicion are exactly where one would be looking this time of year for tropical cyclone genesis.  Below you’ll see the the areas that historically have spawned tropical systems in July.

 

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Over the next several months we are likely to see dozens of areas of suspicion develop in the Atlantic and Caribbean.   Many will likely fizzle . . . but long range forecasts are calling for as many as 20 of these to become named storms. 

 

How many of those will make landfall is unknown.

 

Some years, the pattern keeps most of the storms well out to sea, such as we saw in 1995.  There were 19 named storms, but only 4 made landfall in the United States.

 

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Other years, we aren’t so lucky. 

 

Which means that if you live within reach of one of these storms (and that can be hundreds of miles inland), you need to be reviewing your hurricane plans now.


Not because any of these 4 areas of suspicion pose an immediate threat  . . . but because this is the start of what is likely to be a long and active hurricane season.

 

May was National Hurricane Preparedness week, and during that month this blog devoted considerable time to the subject.  A few of my blogs on the subject included:

 

A Hurricane Reality Check
National Hurricane Preparedness Week: Day 6
NOAA 2010 Atlantic Hurricane Outlook
The Worst That Could Happen
Hurricanes and Inland Flooding
Why I’ll Be Gone With The Wind
Storm Surge Monday
The Crossroads Of The Atlantic Storm Season
You Don’t Have To Live On The Coast

 

Some essential hurricane resources to get you started include:

 

http://www.fema.gov/hazard/hurricane/index.shtm

http://www.ready.gov/america/beinformed/hurricanes.html

 

You may also wish to revisit my blog entitled Hurricane Resources On The Net for links to storm resources online.