Winter MESS 2011

...WINTER STORM WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING...

Complications in this forecast…how warm do we actually get at the surface tomorrow? I’ll try to address that right off…MOS shows high temps reaching well above freezing tomorrow afternoon with NAM at 35 and climbing to near 40 overnight, and the GFS at 40. Now…as was the case with the last system, it’s kinda foolish to rely too much on MOS for a situation like this, but I like to go ahead and look at it anyway because at the same time, it would be kind of foolish to NOT look at it. Raw guidance is where I will base most of the forecast on once again though. Raw NAM keeps us at or just below freezing all day Thursday and warms us overnight and puts us back above freezing by early Friday morning. Raw GFS has a slightly warmer look and would imply more of a mix of sleet/freezing rain/rain as it kinda bounces around the freezing mark all day, whereas NAM would imply more freezing rain/sleet all day tomorrow and changing to rain overnight Thursday. I personally don’t really see any reason for it to warm much tomorrow with the lack of insolation and any kind of warm air advection at the surface. With that said…my own personal thoughts are that we will be dealing with primarily a freezing rain/sleet event here in Meridian for most of the day tomorrow then gradually mixing in rain overnight and eventually switching over to all rain early Friday morning. However…if I’m wrong, and we do warm above freezing tomorrow, then it will likely be mostly a very cold rain. Either way, though, it looks like it will be a very nasty next few days and potentially hazardous to people on the roads.

So…when will this happen? Models are in decent agreement on this part and it looks like precip could be falling as early as early afternoon, however there is a bit of a dry layer aloft that may delay the precip somewhat.

So…what I’m thinking…tonight we will stay mostly cloudy…lows will drop into the mid-upper 20s (~26) and temps should remain fairly steady around freezing throughout the day Thursday (I personally don’t think we will get above freezing until late tomorrow night). Precipitation will continue across the southeast during the morning hours and will gradually spread northward affecting us here possibly as early as early afternoon…starting as freezing rain/sleet more than likely and unless we do get above freezing, which I don’t think we will, it will remain as freezing rain/sleet throughout the day. We will gradually warm above freezing into overnight Thursday and gradually switchover to all rain that will linger into Friday night. I don’t see ANY snow for us here during this event. Again, this is a very fragile forecast and any small error in the warmer direction in temperature prediction would mean a big difference in precipitation type…basically…if we get above freezing tomorrow, we will likely be dealing with mostly a rain event…

I may update this a bit if 0z model data looks any different...