Dry Mays in Relation To South Fla. Hurricanes

[Guest]

Nothing spectacular, but I found this relation to dry Mays & possible hurricane landfalls in South Fla.

The average monthly rainfall total for May in Miami is 6.21 inches.According to the data I was looking at,every hurricane that has made landfall in South Fla. since 1949 occurred after Miami experienced a below average precip total in May.

1949 May rainfall 5.26-Unnamed Hurricane
1950 May rainfall 3.27-Hurricane King
1960 May rainfall 3.47-Hurricane Donna
1964 May rainfall 4.67-2 hurricanes Cleo & Isbell
1965 May rainfall 0.44-Hurricane Betsy
1966 May rainfall 5.53-Hurricane Inez
1979 May rainfall 5.29-Hurricane David (David barely grazed WPB)
1987 May rainfall 4.99-Hurricane Floyd
1992 May rainfall 0.55-Hurricane Andrew
1998 May rainfall was below normal-Hurricane Georges
1999 May rainfall was below normal-Hurricane Irene

The info I was looking at begins in 1948 & ends @ 1997 so I couldn't find the rainfall totals for May before '48 & after '97..I don't know the exact May rainfalls for 98 & 99 the years that Georges & Irene came by but I do know{correct me if I am mistaken} it was below normal.I have no info for those active landfall years in the mid 40's & before, if anyone can provide that data it would be great.I know obtaining that info is not easy.

All that being said....There is a flip side to every story & there were many many years when May had below average rainfall & no hurricanes even came close.

1951- 1.66
1952- 0.68
1953- 3.15
1955- 3.74
1956- 5.44
1962- 0.92
1967- 1.68
1971- 4.13
1973- 1.08
1974- 2.63

& many more years,in fact 14 more years up to '97 that had below average rain in May & no hurricane landfalls in South Fla..Keep in mind though that much of that time from the 70's thru the early 90's we were in that "inactive cycle" that ended in '95.

There does seem to be a better chance of landfalls in South Fla. based on this small amount of data when there is below normal precip in May.I found only 1 year when there was above normal May precip & a hurricane(s) made landfall('48).As mentioned every landfall after that occurred after below normal precip in May.Maybe there is a very slight relation,even though that a "Dry May" does not mean that a hurricane is definitely going to strike,I still think that this info is quite interesting.I wish I had data going back even further but quite frankly I don't know if that even exists.

[Aquawind]

Andrew and Donna..

[smerby]

Hi MIA

I got the precip data from May 98 & 99 for MIA.

98 3.43 inches...62% of normal
99 5.01 inches...91% of normal

Smerby
http://www.accuweather.com

[Guest]

Thanks smerby!

[Patrick99]

What about when you take a dry May, and add a below-normal-rainfall June? I am assuming that June rainfall will be well below normal, as it doesn't seem like there will be any kind of persistent trough over Florida. Who knows, it may change, but....dry weather seems to be begetting dry weather in this case.

I bet that if you take years with a dry May, June, and probably July as well, there will be a stronger correlation with Florida landfalls.

[MWatkins]

All of the extended models out to 144 hours show most of florida under a persistent ridge...and dry as a bone through the next 7-8 days:

http://bricker.met.psu.edu/trop-cgi/avn ... =Animation

MW

[Brent]

I don't really believe in the correlations between those things, but Andrew and Donna

[Guest]

Well Patrick I looked that up & it seems that the biggest correlation occurred with dry Mays.

For example in '49 we had that below normal May but a slightly above normal June..In '60 we had a below normal May & June..In '64 we had a below normal May & another slightly above normal June & from there it continues to flip-flop back -n- forth.

Another example was '92 when May was way below normal & June was around 4 inches over & then we all know what happened later.

So May showed the most consistency compared to the other months.