While I missed the weak tropical storm for the beginning of the last week hitting around Florida, it appears that I was just a week too early. The problem with this story is it could be a much more formidable storm. On Sunday, Tropical Depression 18 formed in the western Caribbean and currently sits as Tropical Storm Rina about 100 miles off the coast of Honduras. Based on the upward motion pattern in the southwest Atlantic and Caribbean, the pattern screamed for a storm and we now have one. Currently a Tropical Storm Watch is out for the coast of Honduras.
Given the weak steering currents over the southern Gulf and western Caribbean Rina will be in no hurry to move. It is drifting to the north and north-northwest at 7 miles per hour. No real acceleration is anticipated for several days letting this storm sit over warm waters and deepen over that time period. At this time it appears that the storm system that will cross the eastern half of the United States for the middle and end of this upcoming week will have no affect on Rina.
The big debate then centers on where will Rina track and how strong will she be? At this time of year with cold air in Canada poised to come down and left over summer heat still trying to hold on in the south, when you throw a tropical disturbance into the mix the models struggle on how to handle the situation. Case in point on Saturday morning runs, a deep, wound up storm was targeted for the Ohio Valley. The Global Forecast System model (GFS) hammered the area with copious rainfall amounts and the potential for a bit of snow on the back end while another model run the European suggested the threat for a major early snowstorm. Just to make matters more complex, both had the tropical energy in the Caribbean being gobbled up and entrained into the end of week storm. Fast forward to Sunday, both backed off the cold, both backed off the copious amounts of precipitation, and both backed off the entrainment idea. Model Mayhem at its best.
Of a more concerning manner is where does Tropical Storm Rina go during its time of existence. For the second time over the last couple of days two hurricane models, the Geophysics Fluid Dynamic Laboratory model (GFDL) and the Hurricane Weather Research and Forecasting Model (HWRF) are suggesting a potential major hurricane. The latest run paints an ominous sign for southwestern Florida.
First the HWRF:
This model shows a hit late on Friday in southwestern Florida. At its peak winds could reach 147 knots which equates to a 169 mph storm. This places the storm as a Category 5 on the Saffir-Simpson scale.
Now the GFDL:
The GFDL model echoes the HWRF in track and intensity. It suggest a southwest Florida hit in the Friday time period. At its peak the model has winds reaching 148 knots or 171 mph; again a Category 5 on the Saffir-Simpson scale.
Now before some of you start to sweat and panic remember this is a model and not a forecast. A model simply suggests what could happen if all the conditions come together during a sample. Several more model runs will come out and a different outcome could occur. The intriguing part, as I mentioned prior, is that the models have suggested a very powerful hurricane more than once. How all of this will play out remains to be seen but it does fit the pattern that we have been seeing for a storm.
Briefly touching on the short to mid range time period for our weather, pleasant temperatures are expected for Monday and Tuesday across the region. Highs on Monday should reach the low 60s in the north to near 70 in the south. Tuesday appears to be the pick of the week with increasing clouds and temperatures in the upper 60s to upper 70s. Rain chances move into western portions of the region by late afternoon Tuesday and will last through Thursday. Rainfall of one to two inches can be expected from this storm system. By the time the school or work week comes to an end, drier weather will move back in but temperatures will struggle in the upper 40s and low 50s but confidence is not the highest based on past storms loving to throw curve balls into the forecast so check back for more information when more pieces of the puzzle fall into place.
For instant updates check me out at twitter @ http://twitter.com/OhioValleyWx or on facebook @ http://www.facebook.com/OVWeather
By Weather Specialist Josh Ketchen