The weekend was nice and that time was welcomed. Rivers stages fell over the weekend but still elevated with the run off from past storms. This has me concerned with the expected rainfall for the week. The Vermilion River is just below flood stage in Lafayette at Surrey Street, 9.1′ Sunday AM October 25, 2009, Flood Stage is 10′. Flooding generally occurs in Parks and Recreation areas along the river at that level. The river originates at Bayou Fusilier, which is fed by Bayou Teche, winds its way through Lafayette Parish, and drains into the Vermilion Bay below Vermilion Parish.
During times of heavy rain events, parts of the Vermilion will reverse itself and flow north. The reverse flow phenomenon occurs because of the highly developed watershed areas in the City of Lafayette. Rainfall runoff from the urban areas in Lafayette Parish enters the Vermion River with larger volumes and at a faster rate. This raises the water level in the Vermilion River along the southern areas of the City of Lafayette. That rise in water levels sometimes exceeds the water level which reaches upstream of Lafayette, thus causing the “reverse flow effect”. Also when water levels in the Vermilion River exceed certain stages, water begins to enter the Bayou Tortue Swamp Area. This swamp has a very large capacity to hold water, which also contributes to the reverse flow effect. The water from the Vermilion River enters Bayou Tortue Swamp through two Coulees. Coulee Crow and Bayou Tortue are located upstream of the Surrey Street bridge on the Vermilion River.
Add this link to your “Favorites”:
Army Corp Engineers River Stages
http://www.mvn.usace.army.mil/eng/edhd/wcontrol/vermil.asp
Concerning the Severe weather threat for late Monday early Tuesday, conditions do appear that we will see storms that could become severe, this means winds greater than 60mph and isolated Tornadoes. Heavy rain is also likely in Acadiana this week so thats where the concern for flooding begins. Storms will continue to form over the same areas capable of producing high rainfall totals. Right now I am uncertain to the exact point at which the rainfall will begin and where but the forecast calls for and additional area of “Low” pressure to form near Brownsville, Texas and move Northeast over Acadiana. This setup brings high rain totals and severe weather to our area.
Rain chancees start low on Monday but by the afternoon and evening storms will be in the area and the risk of severe weather increases. The exact position of the “Low” means everything as far as how much rain and severe weather. I will go with a moderate risk for storms to be severe and the “Low” moving Northeast and just East of Acadiana.
As Low Pressure move Northeast the frron will slow and then on Tuesday stall just to our east. This allows for more rain to develop and for storms moving to North to strengthen and produce heavy rain. For now I will hold off on trying to advertise rain totals for Acadiana and focus more on the development and track of the storm.
Conditions should improve some on Wednesday as the Low moves Northeast dragging the Front through Acadiana allow for some drier air to filter in.
Another system approaches late in the week again we face the threat for storms and heavy rain. With not much time between each weather event high rivers will have little time to drop so any additional rain will be a problem.
Showers and embedded thunderstorms will be likely Thursday. The well advertised frontal trough will continue to draw Gulf moisture northward while the remnants of tropical system Rick gets involved. Combine the aforementioned features with a slow moving upper jet and the result will be occasional rain and embedded storms likely tonight through tomorrow night with the potential for several inches of rain. As Dave mentioned in the previous entry, our flood thresholds are relatively high meaning it would take 3-4 inches of rain before flooding issues could arise, but a “Flood Watch” along with localized run-off problems could certainly be in the mix. This evening’s TrueView model runs continue to indicate a 1-3″ rainfall area-wide with the potential of isolated amounts reaching into the 3-5 inch range somewhere close to home, especially in the southeastern part of Acadiana and the state. In addition to “Rick’s” moisture, there could be a slight severe weather risk in the form of isolated wind damging storms…perhaps a weak tornado potential as well with any pockets of “Left-Over Rick-Spin” so we’ll be on the look-out for that Thursday too. As of press time the 
The forecast seems to still be on track to bring rainfall into the area by tonight and linger through Thursday night. The upper level low over the Four Corners States will eject northeastward today and move toward the mid-Mississippi Valley by early Friday. A cold front will drag along bringing widespread rain from New Mexico through Texas and Oklahoma, and eventually into Arkansas and Louisiana. Heavy rains will fall across much of Texas today and tonight. Moisture from “Rick” is streaming across Mexico, and Gulf moisture is streaming northward over Louisiana. Most of this will be dumped over the ArkLaTex region where flood watches have been posted since yesterday. Significant rainfall will move across Acadiana, with 1-2″ still expected. Flood guidance numbers keep us right under the flood threshold, but that will be monitored. A slight chance for severe weather exists north of us this time around.
Our stretch of great weather will come to an end after Wednesday as a storm system in New Mexico this afternoon should arrive here by the latter part of Thursday. Fair skies with milder conditions are expected for this evening with lows closer to 60 by morning. Wednesday will bring partly to at times mostly cloudy skies with breezy southeast winds. There will be a very slight chance of a passing shower mainly across western sections of Acadiana for Wednesday afternoon. Upper level dynamics should be in place Thursday for rain with embedded thunderstorms to develop Thursday with highest rain chances coming later in the day and perhaps into the evening/overnight hours. As Dave mentioned in the previous entry the threat of severe weather should be limited, but as we say never underestimate “synoptic” systems in an El Nino year. The wild card with this weather system will be how much of Tropical Storm Rick’s moisture will get involved. Locally heavy rainfall will be possible with this system especially 
across Eastern Texas into the Arklatex with amounts in Acadiana still expected to be in the 1-3″ range. We’ll have a better feel for rainfall totals with Wednesday’s computer model guidance…but systems coming across Mexico are usually poorly modeled due to the sparseness of good meteorological data…so we may not have a good feel for where the heavy rain threats are going to be until the storms get cranking across Texas Wednesday night into early Thursday. We should dry out for Friday, but I woudn’t be surprised if after some clear skies additional clouds come back into the area for Friday evening/night. Lingering showers activity for Friday is still possible. The weekend still looks quite good with fair to partly cloudy and mild conditions. Rob
After a gorgeous weekend our weather has stayed spectacular for our Monday (which made this Monday much more tolerable!) but changes are on the way for mid-week. A developing storm in the Rockies will tap into Gulf moisture by Wednesday and perhaps moisture from the remnants of Pacific Hurricane Rick. By Thursday these systems will drag another front across the region allowing for a good chance of scattered showers and storms Thursday. Expect at least a couple of inches of rain Thursday but the wild-cards will be how much of the moisture from Rick and how deep the return Gulf flow gets. Rainfall totals could be as high as 3-4″ with all the decent upper level support, but for now we’ll project 1-3″. There may be a slight severe weather threat as well Thursday so we’ll be keeping an eye on that too. Friday’s forecast looks a little tricky as more stable air in the lower layers should be working it’s way into the region but plenty of upper support and perhaps Rick’s remnant moisture will lag behind. For now we’ll say skies turning partly cloudy Friday with just slight rain chances, primarily in the morning for now…but that could be subject to change. The bottom line though is that we should have another spectacular weekend with lots of sunshine and seasonably cool temperatures! Rob
After a series of lousy weather weekends, I was finally able to show my face in public again with this past weekend’s gorgeous sunshine and cool temperatures. I took last week off of work to spend some time at my house taking care of all of the things that have been put off for so long. You know…fixing stuff, cleaning, getting rid of things I don’t need, and some painting. Being on a normal schedule was nice! So was getting up with the kids and getting them ready for school. Spending quality time with my wife doing all of these projects was probably the best part of my time off. Oh yeah, turning 40 yesterday was a cool milestone too! 
The weekend was sweet and the best part of it…the winds relaxed enough to get out on the Bay Sunday afternoon. Still rough but conditions quickly inproved. Clear your schedule, Monday, and FISH or Boat ride…The pressures are gong to fall some tomorrow and the Prime Times occur during the day. Check out the Fishing Times, 
Picture: NOAA, Hurricane Research Division