Arthur's Short Tropical Life Will Still Produce Significant Rains

By Jay Grymes

Louisiana State Climatologist

The threat for active storms is not over for Louisiana ... but concerns for any widespread severe weather and tropical impacts are on a slow decline for the Bayou State.

Arthur appears to have already moved inland and is expected to remain inland for the rest of 'his' brief journey.  Expect Arthur to be downgraded to a tropical depression Wednesday evening; in fact, Arthur could become a remnant low within the next 12 hours or so.  As of 4 PM, the NHC is showing that Arthur's wind field has shrunk considerably to the north and northeast, taking TS-force winds off the board for Cameron Parish.

Flooding remains Louisiana's primary concern -- mainly across the southern parishes -- as rainbands to the east of Arthur's core will continue to transport Gulf moisture northward with the system's large-scale counter-clockwise circulation.  These rainbands will also be the primary source for any strong-to-severe t-storms capable of potentially damaging winds.  South Louisiana communities need to remain on-guard for rogue t-storms capable of tornadic spin-ups as well, although the threat is low.

WPC forecast rain amounts over the next 2 to 3 days have decreased considerably from the Monday and Tuesday forecasts.  However, with saturated soils, standing water, and waterways already high, any localized downpours over the next couple of days will be capable of producing additional nuisance and flash flooding and push creeks and bayous into rapid rises. 

Note that the SPC has added a SLIGHT Risk to the previous MARGINAL Risk for severe storms for portions of Louisiana, mainly for tonight into Thursday morning.  

Coastal flooding will run 1-3 feet with inlets potentially reaching 4 ft or more tonight into Thursday before the winds begin to relax late Thursday into Friday.  Those high-water marks are generally manageable for the most part in the areas accustomed to wind-driven surges.

Emergency Managers and river residents should keep a close eye on local rivers over the next 3-5 days, as several river forecasts could see another uptick in the next 12-36 hours.