SW Louisiana Forecast Discussion...The first full week of November ends on a dry note. High pressure controlled our weather for one more day today, but changes will occur for the second half of the weekend. Some clouds began moving into the area today as the moisture hovers just offshore. A very complex and interesting weather situation is unfolding for the next few days, and I will digest it with a fine tooth comb here shortly. A quiet night is in store with Clear skies and light winds. Temperatures will moderate some as a return flow of Gulf moisture has begun. Readings last night were in the mid 40s to lower 50s, but tonight expect temperatures to bottom out in the mid 50s to lower 60s across the area. Clouds will continue to increase overnight with the cirrus shield enveloping the entire forecast area towards morning.
The next rainmaker is still on track for late Sunday through early Tuesday. As I've stated throughout the week, a number of elements will work in tandem to engender rain chances beginning Sunday night. The influx of moisture and associated weak surface low over the SW Gulf of Mexico is surging Northward as SW winds over the Gulf increase out ahead of the next advancing trough and attached cold front. At the same time, Ida, which has become a hurricane once again tonight in the Caribbean over the Yucatan Channel, will be moving into the SE Gulf of Mexico. The pressure gradient will tighten across the Gulf coast in response to the pressure differences between the two low pressure systems and the departing high pressure. Winds will increase over land and especially over water because of this, and as a result some coastal flooding issues are expected along the coast from Jefferson County in SE Texas through Iberia and St. Mary Parish in SW Louisiana. More on the coastal flooding situation in a bit. The surge of moisture will lift Northward throughout the day Sunday, and by late Sunday it will be moving inland across the forecast area. Rain and a few thunderstorms will invade the forecast area at this time. Rain could be heavy at times starting Sunday night, but no severe weather is expected. As the clouds and wind increase during the day Sunday, mild conditions are expected temperature wise with maximums expected to be in the mid 70s. Much of the day Sunday will be dry, but a rain chance is inserted for the afternoon hours as some scattered activity is expected as the moisture influx moves in.
Hurricane Ida will be moving into the Gulf Sunday afternoon, and it will appear as though it is on a crash course for the Louisiana coast with a NW heading, but this is not the case. While conditions are favorable for strengthening in the Caribbean and extreme Southern Gulf, a more hostile environment awaits Ida by Monday when it enters the Central Gulf. Strong SW shear will be present across the Northern and Central Gulf waters in response to the advancing trough, and this is not what tropical systems like. The shear as well as much cooler sea-surface temperatures in the aforementioned region will result in the commencement of a weakening trend. The strong winds over the Gulf will steer Ida. Ida should begin a more N to eventually NE motion, perhaps brushing by extreme SE LA, before heading towards the Northern Gulf coast between Mobile and Apalachicola. However, the transition from a tropical entity to extratropical entity will occur, and landfall of a late-season tropical system is not expected. Ida will essentially merge with the non-tropical low in the SW Gulf as the cold front approaches East Texas. This will basically just mean a big wind and rain storm for the Gulf coast with the worst of the weather over the SE US from Mississippi to Georgia. Louisiana will certainly not be left out of some interesting weather with all of this going on. As stated previously, our rain chances commence late Sunday, and will be more affiliated with the SW Gulf non-tropical low and the approaching front as opposed to Hurricane Ida, but as the systems merge Monday this will certainly help to increase rain chances further. In this set up, no severe weather expected here, as we will remain on the better side of Ida, but points Eastward from near New Orleans across to the Florida Panhandle may have to deal with a severe weather threat as well. While it appears the heaviest rain and more serious issues will be to our East, we are certainly still in line for significant rainfall amounts of 1-3" for this event with the majority of said rain coming on Monday. I don't anticipate the expected rainfall to exacerbate the river flooding situation a whole lot, but we'll see how things unfold. Monday will be a day with a small diurnal range with the clouds and persistent rain. Expect a morning low near 60 while the afternoon high will only be near 70. Winds will be an issue as well with occasional gusts up to 30 mph especially near the coast. A strong onshore flow is expected from Sunday through early Tuesday. It'll be Tuesday when the actual front gets here to improve conditions across the forecast area. I will have more on Ida in the tropical section, but here is a rainfall accumulation graphic from the HPC for a 5 day period today through Thursday. All of the expected rainfall will occur from Sunday night through Tuesday morning.
Until the low departs, the weather will be very interesting as we watch the evolution of Ida and the SW Gulf low. The merger that is going to occur isn't something that happens in the Gulf very often. This typically occurs off the Eastern Seaboard as tropical systems move up the East coast and get caught up in the trough that ultimately led to its movement. It is not a rare event for a tropical system to morph with a trough, it's just a bit unusual for the Gulf. The front will slow down a bit as it moves into the forecast area as it feels the influence of some stronger SW winds aloft, but it will have no trouble coming through as the upper level flow away from the Gulf coast will help drive the front past the area. Look for frontal passage to occur from NW to SE across the forecast area late Monday through Tuesday morning. Rain chances are maintained into the morning hours on Tuesday, but conditions will greatly improve in the wake of the front Tuesday afternoon with the area becoming influenced by high pressure once again. Wind will remain a factor with the sharp pressure gradient in place until the extratropical system gets out of the way. A much drier and cooler air mass will replace the deep tropical air mass. Temperatures begin cooling off on Tuesday morning with a low in the upper 50s to around 60, with not much of a diurnal range during the day Maximums should remain in the mid to upper 60s as a CAA regime is established behind the front. Winds will make the switch from onshore to offshore in the wake of the front, but remain gusty on the order of 20-25 mph with gusts to near 30 mph at times on Tuesday. As high pressure begins to build in, beautiful weather will return during the afternoon Tuesday with the sun making an appearance.
Quiet weather controls the forecast for the rest of the work week as another ridge of high pressure builds in across the forecast area from the Mid West. Winds will gradually calm down over land and water as the pressure gradient relaxes. The actual extratropical low could still be over the Gulf at mid-week, but it won't bother us in any way, shape, or form beyond Monday. Clear and cool nights and sunny and pleasant days are expected starting Tuesday night through Friday. No major cold air is expected behind this front, but certainly some of the coolest weather so far this season is expected. Lows will be the in the 40s and 50s each morning, while highs will be in the 60s and 70s. The coolest morning will likely be Thursday as the high moves fairly close by, and causes winds to relax across the area. Low to mid 40s are feasible for Thursday morning. A moderating trend begins for Friday as the high slides East along the Gulf coast, but very pleasant weather is to be expected.
A progressive weather pattern will continue through the forecast period. The next trough will be digging into the Great Plains at week's end, and the upper flow will allow for another cold front to head our way on day 7...Saturday. Modest moisture return from the Gulf will occur as the mid-week high departs on Friday. Some rain is possible ahead of this front on Saturday, but due to some model inconsistencies at this time I will preclude any rain chances, and just note cloud cover at this time in the official forecast. Moderating temperatures are expected at this time with the Gulf opened up once again. Lows should be well up into the 50s for Saturday while highs top out in the mid 70s. The extended offers the usual uncertainties, but another nice cool down should follow the front at day 7. There are discrepancies about whether or not we'll clear out behind this front, or perhaps see some overrunning. Beyond mid-month, a progressive pattern continues, but no model run offers any clear solution about what will unfold.
Tropics: Ida is a hurricane again...Ida, which briefly reached hurricane status before making landfall Thursday in Nicaragua has steadily strengthened since emerging into the Western Caribbean Sea Friday. It is a very favorable environment for strengthening, and its current location is a prime area for development in November. It's satellite representation is one that is stronger and healthier than it has been throughout its entire life cycle. It is at its peak intensity so far with winds of 90 mph, and it could reach category 2 status later on Sunday. It's current position is about midway between Western Cuba and the Yucatan Peninsula in an area where water temperatures remain well into the 80s. Ida will be moving into the SE Gulf of Mexico on Sunday. While strengthening is expected initially, Ida's life cycle is running on borrowed time. Ida will begin to weaken as it moves further into the Gulf on Monday. There are many factors in place that will result in the weakening trend. Sea-surface temperatures are far below the necessary threshold to support tropical development. Wind shear will be increasing across the Central and Northern Gulf ahead of an approaching cold front. A non-tropical low in the Bay of Campeche will lift Northward towards the Northern Gulf coast at the time, and as both systems get caught into the shear environment over the Gulf Ida will transition from a tropical entity to an extratropical entity. Strong winds and high seas will impact a large portion of the Gulf of Mexico during the first half of the work week, but an acutal U.S. landfall of Ida is not expected. The extratropical low will move very close to the tip of SE Louisiana, and towards the Northenr Gulf coast perhaps paralleling the coast between Mobile, AL and Tallahassee, FL. Some models indicate that the low pressure will remain over the Gulf through much of the week, but with the advancing front absorption of the system is likely. Heavy rain is expected for the first half of the week across a large portion of the Gulf coast from the remnants of Ida.
Hurricane Ida
Sunday, November 8, 2009 10p.m. CST
Latitude: 20.2 N
Longitude: 85.4 W
This position is about 100 miles ESE of Cozumel, Mexico or 110 miles SSW of the Western Tip of Cuba.
Winds: 90 mph w/ higher gusts- Category 1. Additional strengthening is expected today, and Ida could reach category 2 status later today. Hurricane force winds extend outward to 15 miles from the center while tropical storm force winds extend outward to 140 miles from the center.
Movement: NW at 10 mph. A NW or NNW motion is expected for the next couple of days with an acceleration in forward speed expected. Ida will be moving through the Yucatan Channel near the NE tip of the Yucatan Peninsula and into the SE Gulf of Mexico later today.
Pressure: 29.03" or 983 mb.
Watches and Warnings...A Hurricane Warning is in effect for the coast of Mexico from Cabo Catoche to Playa del Carmen. A Hurricane Watch is in effect for the coast of Mexico from Playa del Carmen to Tulum. A Tropical Storm Warning is in effect for Grand Cayman Island, and for the coast of Mexico from Punta Allen to San Felipe, as well as the Cuban Province of Pinar del Rio. A Tropical Storm Watch is in effect for the Isle of Youth.
Elsewhere, the tropics are quiet.
River Flooding...River flooding continues mainly on lower portions of area rivers now as the water associated with the recent heavy rains continues to flow downstream. The strong offshore flow will cause tidal backup on the lower Neches, Sabine, and Calcasieu Rivers through Monday. Additional rainfall is expected beginning tonight through Tuesday morning; this could lead to some revision of river stages in the coming days.
Sabine River
Location Flood Stage Current Stage Crest
Bon Wier 30' 34.9' Fall Below FS Monday AM
Deweyville 24' 27.8' 27.9' Sunday PM
Orange 4' 2.5' 4.2' Monday PM
Neches River
Location Flood Stage Current Stage Crest
Town Bluff 64' 65.2' Holding Near Current Level
Beaumont 4' 3.5' 4.1' Monday PM
Calcasieu River
Location Flood Stage Current Stage Crest
Glenmora 12' 12.8' Fall Below FS Wednesday PM
Oberlin 13' 13.4' Fall Below FS Sunday PM
Salt Water Barrier 4' 4' Hold Steady
Old Town Bay 4' 4.6' 4.8' Monday AM
Coastal flooding is expected for the next couple of days due to the impinging storm. Tide levels will be near 1' above normal astronomical tide levels, and this will result in tide levels near 3-4' at times near high tide on Sunday. Minor coastal flooding is expected at these times. Water may cover portions of Highway 82 in Cameron Parish between Cameron and Johnson Bayou, and Highway 87 in Jefferson County between Sabine Pass and Port Arthur.
Preliminary Numbers & Zone Forecast:
LCH 58/75 60/70 57/67 0 30 70 80 60 30
LFT 56/76 59/72 59/68 0 20 70 80 70 30
BPT 59/77 62/71 58/70 0 30 60 70 50 20
AEX 51/76 58/68 55/65 0 20 60 70 50 30
POE 52/77 59/68 56/66 0 20 60 70 50 30
ARA 56/76 60/73 60/70 0 30 70 90 70 40
*Coastal Flood Watch in effect through Sunday.*
Tonight...Partly Cloudy. Low 58. East wind 5-10 mph.
Sunday...Mostly Cloudy with a 30% chance of rain and a few thunderstorms in the afternoon. High 75. East wind 10-15 mph.
Sunday Night...Cloudy and windy with rain and a few thunderstorms becoming likely. Heavy rain at times. Low 60. East wind 15-20 mph and gusty. Chance of rain 70%.
Monday...Cloudy and Windy with rain and a few thunderstorms likely. High 70. ESE wind 15-20 mph with gusts to near 30 mph at times. Chance of rain 80%. Rainfall totals 1-3" from Sunday night to Monday night.
Monday Night...Cloudy and Windy with a 60% chance of showers and thunderstorms. Turning Cooler Late. Low 57. SSE wind becoming NNW 15-20 mph with gusts to near 30 mph at times.
Tuesday...Cloudy with a 30% chance of rain in the morning, becoming Sunny in the afternoon. Windy and Cooler. High 67. NNW wind 15-20 mph and gusty.
Drew's 7 Day Outlook for Lake Charles & Vicinity
Sunday
11-8-09
Low: 58
High: 75
Rain: 30% PM
Wind: E 10-15
Monday
11-9-09
Low: 60
High: 70
Rain: 80%
Wind: SSE 15-20
Tuesday
11-10-09
Low: 57
High: 67
Rain: 30% AM
Wind: NNW 15-20
Wednesday
11-11-09
Veteran's Day
Low: 50
High: 66
Rain: 0%
Wind: N 10-15
Thursday
11-12-09
Low: 46
High: 69
Rain: 0%
Wind: NE 5-10
Friday
11-13-09
Low: 49
High: 72
Rain: 0%
Wind: ESE 5-10
Saturday
11-14-09
Low: 55
High: 74
Rain: 0%
Wind: SSE/NNW 10-15
...Marine Forecast...
*Small Craft Advisory. *
Synopsis...MODERATE TO STRONG EAST TO NORTHEASTERLY WINDS WILL CONTINUE THROUGH EARLY MONDAY AS THE PRESSURE GRADIENT CONTINUES TO TIGHTEN BETWEEN STRONG HIGH PRESSURE ALONG THE EAST COAST AND A DEVELOPING TROUGH OF LOW PRESSURE OVER THE SOUTHWESTERN GULF. THE TROUGH IS EXPECTED GRADUALLY MERGE WITH TROPICAL CYCLONE IDA MONDAY. THE COMBINATION OF IDA TO THE SOUTHEAST AND STRONG HIGH PRESSURE TO THE NORTH WILL RESULT IN A SIGNIFICANT OFFSHORE FLOW DEVELOPING...WITH VERY HIGH SEAS DURING THE PERIOD.
Tonight...East winds 10 to 15 knots. Seas 2 to 3 feet.
Sunday...East winds 15 to 20 knots. Seas 2 to 4 feet building to 3 to 4 feet in the afternoon. A chance of showers and isolated thunderstorms.
Sunday Night...Northeast winds 20 to 25 knots. Seas 3 to 5 feet. A chance of showers in the evening. A slight chance of thunderstorms. Showers likely after midnight.
Monday...Northeast winds 20 to 30 knots. Seas 3 to 5 feet. Showers likely and a slight chance of thunderstorms.
Monday Night...North winds 20 to 25 knots. Seas 5 to 7 feet building to 6 to 9 feet after midnight. A chance of showers.
Tuesday...North winds 15 to 25 knots. Seas 6 to 9 feet.
...Tide Data...
Sunday Tides:
Low: 12:03a.m. 12:45p.m.
High: 12:41a.m. 9:08p.m.
...Toledo Bend Pool Level...
172.52'
...Lake Charles Climate Summary...
Saturday, November 7, 2009
Low: 50
Normal Low: 52
Record Low: 30-1959
High: 78
Normal High: 73
Record High: 89-1924
Rainfall
Today: 0.00"
Month to Date: 0.00"
Normal Month to Date: 0.99"
Year to Date: 61.94"
Normal Year to Date: 48.97"
Record: 1.67"-1943
Sunrise Sunday: 6:33a.m.
Sunset Sunday: 5:20p.m.
Hunting Times: 6:03a.m.-5:50p.m.
Have a good weekend!
Good night and God bless!
-DM-
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