WEDNESDAY EVENING CRISTOBAL UPDATE from Meteorologist Scot Pilie — Tropical Storm Cristobal now over southern Mexico, movement is stationary, and it has weakened slightly with max winds of 45mph.
Expected to turn north by Friday with growing potential for impacts in Louisiana and the Gulf Coast this weekend into early next week from Cristobal.
I have put Louisiana within the “Pay Attention Zone,” as impacts are likely late Saturday-Tuesday; however, the degree of impacts remain uncertain. Primary risk looks to be rainfall & coastal flooding, but some wind impacts possible as well.
I would review your hurricane safety plan & make sure you’re fully prepped with the essentials, just in case.
The system has officially made landfall in Mexico, and the amount of time it spends on land will be critical to its long term strength.
More time on land = weaker/sloppy tropical storm. Less time on land = stronger tropical storm or even hurricane by this weekend.
Rainfall, storm surge, and wind impacts are unclear at this stage. But, I would be prepared for the potential for some form of heavy rainfall, coastal flooding outside of levee protection, and some wind.
Flash Flood Watch —
In effect from 10AM Wednesday until 7AM Tuesday. Rainfall 4-6” likely w/ localized 10+”. Expect rainfall amounts to change based on Cristobal’s track.
Remember, Thursday-Friday — Scattered localized heavy downpours. Street flooding risk with slow movers. Not a rain-all-day type of setup.
Late Saturday-Tuesday — More numerous showers and thunderstorms with the arrival of Cristobal. Amounts will vary widely depending on where tropical feeder bands become established.
Impacts could begin as early as Saturday. With minor coastal flooding even possible Friday with persistent onshore southeasterly flow outside of levee protection.
Some additional key points:
A big factor/wrench in the forecast with Cristobal will be how much dry air becomes entangled with the system by Saturday-Monday, especially as the system slows down as it approaches landfall by late Sunday-early Monday.
More dry air = weaker/lopsided system. More dry air will displace heaviest rain well east of the center. This could keep the worst of the rain east of Louisiana altogether.
Less dry air = more organized. Greater potential for heavier duty rainfall risk.
Remember Barry last year? Dry air saved lots of folks from seeing copious flooding rainfall totals. We will have to watch the evolution…