Ticker for April 30, 2009

                
MESONET TICKER ... MESONET TICKER ... MESONET TICKER ... MESONET TICKER ...
April 30, 2009     April 30, 2009     April 30, 2009     April 30, 2009


Have Ark, Will Travel

Climatologists get so few chances to get excited about weather. Go up to your
average climatologist and say "Hey, it sure was cold last night!" and you'll
probably get a sneer and an "Oh yeah, how does that affect the 30-year
normals?" in response. Some of us carry pictures of temperature exceedence
tables in wallets instead of snaps of our kids. So when we see a day like
Burneyville had yesterday, we all huddle together in small bunches and
excitedly discuss a multitude of broken records. Disco, preferably.

Rainfall records fall by the wayside

Between 10:50 a.m. Wednesday and 5:10 a.m. Thursday, the Oklahoma Mesonet site
at Burneyville recorded 12.89 inches of rainfall. A momentous amount of rain
no doubt, and that total is obviously going to break some records. Now you
are probably saying to yourself ?But Gary, doesn?t Mesonet measure from
midnight-midnight, while COOP measurements can be 7am-7am, 6pm-6pm, etc??
First off, that?s a weird thing to be saying to yourself unless your name is
Gary, but point well taken. Keep in mind as we discuss these that we are in
somewhat uncertain territory due to the different periods Mesonet vs. COOP
use in their measurements. There is also the distinction
between 24-hour records and daily records. These and other considerations
have all been...uhhhh...considered.  In the end, if we want to stick strictly
to midnight-midnight periods, we have a total of 12.42 inches with this event,
so we?re still safe. We?ll go with our ?daily? total (7am-7am) of 12.89
inches where appropriate.

So let's go through what records we now believe have fallen.

1. Burneyville daily rainfall ? All we have to go by is the Mesonet station
since it appears there was never an official Burneyville  NWS COOP site.
The total obviously shattered the previous daily record for Burneyville,
6.62 inches set on April 28, 2006.

2. Burneyville monthly rainfall ? The single day total was enough to best
the previous monthly total of 12.01 inches from June 2004. Add in rain
from earlier this month and you have a monthly total that currently
stands at 15.36 inches.

3. Mesonet daily rainfall ? The total shatters the previous daily rainfall
mark recorded by the Mesonet of 9.89 inches at Cheyenne on June 14, 1996.
The only other totals in view of this one would be the 9.13 inches at
Fairview on September 12 of last year and the 9 inches recorded at
Fort Cobb during Tropical Storm Erin?s recovery on August 18, 2007. A
more thorough investigation shows the Burneyville event broke the 24-hour
rainfall event for the Mesonet as well. No 24-hour period in the history
of the Mesonet had a greater total than 12.89 inches.

4. Oklahoma daily rainfall amount, any network ? The total of 12.84 inches
has been bested only three times in our recorded history. The rankings:

Enid (COOP), October 11, 1973               15.68 inches
Cheyenne (COOP), April 4, 1934              13.79 inches
Purcell (COOP), May 11, 1950                13.58 inches
Burneyville (Mesonet), April 29, 2009       12.89 inches
Eufaula 2 SW (COOP), October 31, 1941       12.86 inches
Stigler 1 SE (COOP), May 10, 1943           12.32 inches
Hee Mountain Tower (COOP), October 13, 1972 12.30 inches
Seminole (COOP), April 14, 1945             12.20 inches
Meeker (COOP), June 3, 1932                 12.18 inches
Seminole (COOP), June 22, 1948              12.00 inches

5. Recurrence-interval totals - While these aren't records, they are a good
indicator of extreme rainfall events. These are taken from Tortorelli's
"Depth-Duration Frequency of Precipitation for Oklahoma" publication.

Recurrence Interval         Tortorelli      Total
500-Year 1-Day              12.20         12.89
500-Year 24-Hour            12.00         12.89
500-Year 12-Hour            10.80         11.73
100-Year 6-Hour              6.80          8.58
100-Year 3-Day              11.60         12.89
50-Year 7-Day               11.80         12.92

That's all we have for now. The Ticker staff are all data-mined out. Stay tuned
to this channel, however, for a sequel to this movie called (cue eerie music)
"THE DARKEST DAY IN BURNEYVILLE (and possibly Mesonet) HISTORY!"

Thanks for the tip on that one, Jacob.

Whoops, kill the eerie music.

Gary McManus
Assistant State Climatologist
Oklahoma Climatological Survey