Forecast continues to be complicated and tricky given recent trends of the upper trough energy cutting off more to our south,though still a lingering shortwave influencing the TN valley and some isentropic upglide potential along a lingering hybrid wedge for Monday. Timing has shifted overall a bit later than previous runs as far as when the best moisture/forcing is present in our NW... thinking mainly after 7 AM is best chance for parts of the NW to see some light freezing rain. Overall amounts have come down from before (generally less than a tenth of an inch for north and west central GA), though may not matter much since impacts with any ice accumulation on roadways would not change much (higher amounts would be of more impact to trees/powerlines). As far as temps, there still looks to be a decent majority of north and parts of central GA below the freezing mark or right around by Monday morning...the Canadian and Nam and the coldest, though the Nam is pretty dry and actually delays the precip until late morning or even afternoon. The GFS still has the NW with a morning onset (that could include the Atlanta metro). Some sounding analysis indicates potential for a low/mid level column of lingering drier air that saturation aloft could be battling, otherwise some higher QPF could be a factor. Not thinking anything warrants a Winter Storm Watch at this point, but may need a Winter Weather Advisory for some portions in future updates as we get closer - though likely have changes in timing/amounts. Good afternoon. Here's the latest from the Atlanta National Weather Service office in Peachtree City regarding the potential for freezing rain and icing Monday. First, the text below is from the latest Area Forecast Discussion: ------------------------------------------------------------------------------- Obviously focused on late Sunday through Monday period with the update as we are getting more guidance consensus (albeit the latest Euro) on some freezing rain potential within a lingering hybrid CAD wedge. Nam and the Canadian continue to be the coldest/more robust solutions and the GFS ensemble members have all but a few indicating some freezing rain including the Atlanta Metro by Monday morning pretty much centered around 7 AM. Thermal profiles support some possible sleet transition and not much chance for snow, though primarily freezing rain given a pretty thick warm nose overrunning the wedge. Big question remains on the onset timing of precip and diabatic in-situ reinforcement potential of the wedge. Kept the temp trend slower to warm into Monday given this. Most locations should get above the freezing mark by mid to late morning. Also ended up fairly close to WPC QPF in the period and adjusted the ice accumulations to mainly upwards of 2 tenths of an inch though greater chance for closer to 1 tenth extending generally from south metro farther north. WPC keeps us in primarily the less than 1 tenth range. Will update accordingly and will need to consider Watch/Advisory products if confidence increases in this, but still too far out in period to include (also if the much drier Euro starts to trend in consistency). |
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