Ticker for July 23, 2008

                
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July 23, 2008      July 23, 2008      July 23, 2008      July 23, 2008



Hello, Dolly?

With Dolly's landfall along the U.S./Mexico border today, a natural
question to ask is "Will we get some rainfall with this?" And our
answer is ...

"We don't know. Ask a decent forecaster."

Yeah, that's a copout. Actually, the forecasts are not very optimistic
that Dolly will help out with precip.

Anyway, we decided to look into the role of landfalling tropical storms
on our July and August rainfall. We expected to confirm the myth
(largely propagated by The Entire Ticker Staff) that we need tropical
systems to get big rainfall in July and August.

Well, turns out that the data says that myth isn't entirely true.
Take a look at the following graph that shows:

Pink: July rainfall in CD5 (Central OK)
Mint: July rainfall in CD9 (Southeast OK)
Red: August rainfall in CD5
Green: August rainfall in CD 9



Reference Map: 


We've marked up the wet months that were directly influenced by a
landfalling tropical storm. This graph underscores a few points:

1. Maybe landfalling tropical systems aren't the mid-summer
rain-makers they are made out to be.

2. The footprints of imapact are smaller than you might think.
Even the events that caused localized flooding (Dean, Aug 95;
Alicia, Aug 83; Erin Aug 08) didn't leave a huge mark on
a climate division scale.

3. We should point out that Sep and Oct are also in the mix.
We haven't examined their totals yet. October is historically
known for being The Month In Which Tropical Storms Can Wreak
Havoc With Flooding.

4. Tropical storms/systems are still important in mid-summer, even
if they don't directly escort the rains to the state. The
moisture they provide is often picked up by other rain-making
mechanisms. This was the case in in July and August 1996, when
remnant moisture from long-gone storms Boris (Pacific) and
Bertha contributed to heavy rains.