Thursday, August 6, 2009

Rain Chances Increase Slightly Over the Weekend...

Thursday, August 6, 2009

SW Louisiana Forecast Discussion…August is off to a dry start thanks to the persistent upper level ridge that dominated the weather across SW Louisiana again today. There was not much in the way of shower and thunderstorm activity across the area today with the exception of coastal sections of Acadiana. An area of more widespread shower and thunderstorm activity occurred across the Northern half of the state as an MCS associated with an upper level disturbance moved from NE to SW across that area. With the effects of the afternoon sea breeze, and daytime heating, and the upper level disturbance in close proximity, the Storm Prediction Center in Norman, OK issued a severe thunderstorm watch for all of Western Louisiana this afternoon. This was with the anticipation that more shower and thunderstorm activity would develop during the late afternoon and evening hours. However, this never materialized due to a cirrus canopy which moved over the area from the thunderstorms off to our NE. This inhibited temperatures from reaching their maximum potential today, thus limiting the shower and thunderstorm activity. I generally don't like to disagree with anyone at the Storm Prediction Center as they do a very good of forecasting severe weather, but this was one time when I felt that a watch was not prudent.

A quiet night is in store across the area with typical August mosquitoes and humidity in place. Low temperatures will be in the mid to upper 70s as usual. On Friday, the ridge in place intensifies temporarily, and this will quash the majority of shower and thunderstorm activity across the area as well. A few showers and thunderstorms will develop during the hours of 3-7p.m. via the sea breeze. Any shower or storm that does develop will quickly dissipate by sunset. Temperatures will be above normal with the ridge in place. Expect highs in the mid 90s for most locations with upper 90s in the typical hotter locales north of US 190. Heat indices will be in the 100-105 degree range, so it will be plenty hot as usual, but this is not heat advisory criteria, as falls well short of the excruciatingly hot weather we had in June. This pattern will continue into Saturday, but the ridge will start to shift Eastward at this time. Thus, rain chances will increase slightly for Saturday. The position of the ridge will allow for a deep Southerly flow to develop across the area enabling the usual sea breeze activity to produce about average coverage of shower and thunderstorm activity. Temperatures will remain in the mid 90s for Saturday with seasonable morning lows forecasted.

By Sunday, as the title suggests...rain chances increase. The ridge will be centered over the SE U.S. at this time, and this will not only favor a deep Southerly flow, but also allow for any disturbances embedded in the overall upper air pattern across the country to rotate around the periphery of the high. With a deep flow of moisture of the Gulf, this will result in more cloud cover, and with the effects of daytime heating and interaction of the sea breeze, more of the daily dose of cumulus clouds will undergo vertical growth during the late morning and early afternoon hours. Expect about half of the area to see shower and thunderstorm activity on Sunday. Temperatures will be slightly cooler as well with the higher rain chances in place. This pattern should hold into Monday with about half or a little less than half the area getting some relief.

Subtle changes occur in the latter stages of this forecast period. The ridge re-positions itself closer to our area during this time, decreasing rain chances to below normal by mid-week. Temperatures will heat back up as well. Tuesday will be about an average August day as we make the transition to drier once again, but for Wednesday and Thursday the chances of shower and thunderstorm activity are slight at best at this point. The typical daily variances that are present during the summer months will dictate rain chances at this time, but don't expect anything out of the ordinary for August.

Looking long range...No large scale weather systems are expected across the area. The daily variances in atmospheric conditions will be present, and the movement of seasonal high pressure ridges will be the major things to watch in the coming days.

In the tropics...all is quiet in the Atlatnic Basin, but in the Eastern Pacific there is a major hurricane. Hurricane Felicia has weakened a bit since this morning, but remains a category 4 storm with 135 mph winds. It is forecasted to continue weakening as it moves into the colder waters of the Eastern Pacific. Felicia is right in the middle of the Eastern Pacific, and is heading towards Hawaii. It is forecast to affect Hawaii early next week, but should be a much weaker system by then, as it is only forecasted to be a tropical depression or weak tropical storm as it passes near or over the big island of Hawaii early next week. It has been an active thus far in the Eastern Pacific with 6 named storms already, while it is been very quiet on our side in the Atlantic basin...very typical of an El Nino year. I have included the forecast track for Felicia, in case anyone has interests in Hawaii.




Preliminary Numbers and Zone Forecast to follow:


LCH 75/95 76/94 75/92 0 20 0 30 0 50

LFT 76/95 76/94 76/93 0 20 0 30 0 50

AEX 75/98 75/96 75/93 0 20 0 30 0 40

BPT 77/96 76/94 76/92 0 20 0 40 0 50

ARA 77/95 77/93 77/91 0 20 0 30 0 50

POE 75/97 75/95 76/93 0 20 0 30 0 40


Tonight…Mostly Clear. Low 75. Light SE wind.


Friday…Mostly Sunny with a slight chance of afternoon showers and thunderstorms. High 95. South wind 10 mph. Chance of rain 20%.


Friday Night...Mostly Clear. Low 76. Light SE wind.


Saturday…Partly Cloudy with a 30% chance of afternoon showers and thunderstorms. High 94. South wind 10 mph.


Saturday Night…Mostly Clear. Low 75. Light SE wind.


Sunday…Partly to Mostly Cloudy with a 50% chance of showers and thunderstorms. High 92. SE wind 10-15 mph.


7 Day Outlook for Lake Charles & Vicinity

Friday

8-7-09







75/95/20

Wind: South 10

H.I.: 100-105

U.V.: 11- Very High


Saturday
8-8-09








76/94/30
Wind: South 10

H.I.: 100-105

U.V.: 11- Very High




Sunday
8-9-09








75/92/50
Wind: SE 10-15

H.I.: 95-100

U.V. 11- Very High



Monday
8-10-09






75/26/40

Wind: SE 10-15

H.I.: 98-103

U.V.: 11- Very High


Tuesday
8-11-09







75/93/30
Wind: South 10
H.I.: 100-105

U.V.: 11- Very High



Wednesday

8-12-09







75/94/20
Wind: South 10
H.I.: 100-105

U.V.: 11- Very High



Thursday

8-13-09







75/95/20
Wind: South 10

H.I.: 100-105

U.V.: 11- Very High



Click the link below for the Marine Forecast:


http://forecast.weather.gov/shmrn.php?mz=gmz450

Lake Charles Climate Summary for Thursday, August, 6, 2009


Low: 77
Normal
Low: 74 Record Low: 62- 1912
High: 94
Normal High: 92 Record High: 101-1913


Rainfall Today: 0.00"
Month: 0.00" Normal Month to Date: 0.88"
Year: 33.71" Normal Year to Date: 34.12"

Sunrise Friday: 6:35a.m.

Sunset Friday:
8:01p.m.





-DM-


1 comment:

  1. Drew, had a chance to read it over and it's looking good. What a great way to convey your vast knowlegde of the weather and the climate variations across SWLA. Hope all is well!
    -Jeff Jumper

    ReplyDelete