Tropical Depression 19 expected to pass close to Naples today (Sept. 12, 2020) (H. Michael Mogil, CCM, CBM, NWA-DS*)
Now, newly-formed Tropical Depression (TD) 19 is set to add significantly more rainfall to already saturated ground and full lakes and canals. Forecasts call for two to four inches of precipitation across southwest Florida, especially along and to the west of I-75 during the weekend (Fig.1). As is always the case, localized amounts may reach double those numbers. Hence, a Flood Watch is in effect for southwest Florida until Sunday morning.
At 2:00 am E.D.T., on Sept. 12, 2020, the center of TD 19 was located just to the south-southeast of Miami, FL. A short while later, the center of the circulation made landfall between Miami and Key Largo. Heavy storms were located near the system’s center at the time (prompting the issuance of a severe thunderstorm warning for parts of Miami-Dade County – Fig 2). The system was continuing its west-northwest movement at about 8 miles per hour.
This land trajectory should still keep the system at tropical depression status until it exits Florida (to the south of Naples) and starts to feed on warm Gulf of Mexico waters later today through tomorrow. The National Hurricane Center’s forecast track brings the system ashore near New Orleans early next week as an almost hurricane (Fig 3).
However, since that time, the system has taken a slight turn to the west. This means that it may not weaken as much as it heads out into the Gulf of Mexico, it may have slightly more time for strengthening over the Gulf, and it may landfall along the central Gulf Coast more to the left side of the “cone” (i.e. more toward central Louisiana).
While strong, gusty winds are likely across south Florida today, note that we are talking about a TD right now. Any wind gusts above 30 miles per hour will likely be linked to individual thunderstorms within the TD’s circulation. One such gust (33 miles per hour) struck Miami International Airport overnight.
So, with heavy rainfall and flooding the main concern, if you must go out…walk or drive…be especially cautious. If water does cover a roadway, presume it is deep and you shouldn’t be walking or driving through it.
Otherwise, monitor reliable TV, radio, and internet sources of weather information for the next 12 to 24 hours, until the TD clears our west coast. Then, just stay tuned to keep up with the daily spate of showers and thunderstorms (some with locally heavy downpours)…UFN.
© 2020 H. Michael Mogil
Originally posted 9/12/20
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