Sunday, July 02, 2006

A clarification

The second comment of a technical nature came in yesterday - from "anonymous."

I guess that we should have specified some ground rules for the blog. Public discussion, regardless of the topic, is not very effective if we don't know who is talking to whom. This, of course, is why newspapers and magazines don't publish letters unless they are signed.

I don't know how things work in the general blogger world, but MadWeather will not accept unsigned posts in the future. We will leave the current "anonymous" post up on the blog, since we had not addressed this issue before it was posted.

I would suggest, if someone has comments but doesn't want to identify themselves, that you contact me directly.


  1. The 2006 Monsoon

    The monsoon started in SE Mexico at the last half of June with heavy flooding in Chiapis. By the end of May thunderstorms dumped above normal rainfall in Chihuahua and Durango......and this spilled into SE AZ during the first week of June with the first attempt at establishing the monsoon (June 6-7). This early arrival was a failed attempt in SE AZ, but in Chihuahua and Durango the rains continued with western sections of these two states having near record June rainfall with 3-5" amounts common and one area with >8" (SMN precipitation maps).

    The monsoon arrived in SE AZ the 21st of June if one uses lightning detection data and radar rainfall estimates. While the old definition of the monsoon failed as Tucson dew points were not at 55F, these other two data sets clearly showed that the monsoon was underway without a break across the broad domain of Pima and Cochise counties. So, why not use these two data sets to define the monsoon as the first 3 day run of lightning being detected with rainfall estimates for at least one area >0.10". The WMO defines the monsoon in NW India and Sub Sahel Africa as the first run of 3 days with single station rainfall >0.5mm and no break greater than 5 days after this first run. The long break is permissable given the spotty nature of rains in semiarid regions. So why not apply a 3 day run of lightning data with daily amounts of at least 0.10" to define the monsoon in SE AZ? This would then be a broader definition for all communities in SE AZ.....not just a dew point criteria for Tucson.

    As for SE AZ, the monsoon

  2. oops.........first time I used this blog so a few mistakes. I thought I could still correct my discussion, but not so!

    Any how, the monsoon started the last half of May in Chiapas.....NOT June.

    My last sentence was going to read:
    As for SE AZ, the monsoon this year appears to have been associated with a quasi stationary low latitude trough anchored west of SW Baja. This trough was associated with a strong subtropical jet that spun up vorticity centers near Mazatlan and these centers then moved north along the Sierra Madre Occidental. It appears that the rains in Chihuhua and Durango were helped out by the cold 500mb temperatures of -8C to -9C with considerable moisture seepage from the Gulf of Mexico through the Rio Grande and mountain gaps in Nuevo Leon.

    The first Gulf Surge did not hit Yuma until July 2nd (see web site at:

    select "Yuma Gulf Surge Index" and then select July 2, 2006.