October 18th-21st Rain Event

There is still some disagreement among the models as of 12 Z today. We are going to take a look at the models and then since they are not in agreement we are going to take a look at the ensembles and see if we can get some better agreement.

12 Z ECM essentially has a disorganized system approaching from the SW..

12 Z UKMET has a system slightly more organized coming from the SW.

The 12 Z GGEM has a primary low that hands off to a secondary that deepens as it moves up the eastern seaboard.

The 12 Z GFS has a low that basically comes up from the southeast and then moves northwards.

So as you can see we do not have complete agreement in the operational models as of 12 Z. So we are going to now turn to the ensemble means and see if we get better agreement among the models!

The above is the ensemble means of the GFS and the ECM. The first thing to notice is the ECM has a much more organized system then the operational model. Then the other thing to notice is that the ensembles agree with one another in moving a system from the south east up towards the NE in what appears to be a due north motion.

Now what we think should occur is the following:

The trough should dig its way towards the south and begin to amplify. While this is occurring a cold front will be moving across towards the east. Low pressure should develop in the south central US and move ENE and then due north up the coast as it is deepening.

While this is all occurring there is a tropical system currently near the Yucatan and this system is going to move into the GOM. This should cause moisture entrainment from the gulf of Mexico to get entrained into the low pressure that will be moving over the southeast towards the North.

This will provide regional rainfall totals of 1-3 inches across the area as shown on the map below.

Now.. the precipitation amounts above could end up verifying higher then what shown depending on what happens with the system in the Yucatan region. We will continue to keep an eye on this and update anything should it need attention!