January 13, 1999
Well, first let me begin by answering a few of my critics as to why I didn't post on Monday
in regards to the possibility of snow on Tuesday morning. My response is simply this, I
had a gut feeling that as the clipper approached from our west, that the mountains would
help to shear it apart. This is exactly what happened justifying my reasons for not posting
on Monday. This is not the first time this winter that the NWS has called for snow only for
us to get nothing. It is also one of the few times that I disagreed with them. Needless to
say, I'm glad I stuck with my instincts on that particular event. Nevertheless, that
non-event is over with and now I'd like to move on to more important things, namely the
possibility of frozen precip later tonight into tomorrow. Computer models as well as
government weather offices have been in almost complete disagreement with this system.
Currently, a stationary front is dangling precariously just to our north. As the day
progresses, this will turn in to more of an arctic boundary, once again, dividing mild air to
the south from the cold air to the north of this front. Precip is occurring along this
boundary and will creep into our area sometime this evening. The evening rush shouldn't
be a problem as far as icy roads. Mild temperatures the past few days have scoured out
most of the cold air at the surface. In short, the ground is above freezing, so it would take
time for any precip, frozen or not, to lower surface temperature to 32 degrees. As nightfall
approaches, any rain showers that we see will turn over to a mix of sleet and some wet
snowflakes, probably close to midnight. As surface temps approach the freezing mark,
snow and ice will begin to accumulate on trees, power lines, bridges and overpasses first,
and then eventually on all surfaces. Precip could become more moderate towards dawn as
mid-layer temps cool enough to possibly turn the mix over to just snow for a short period
of time. Thereafter, it's anyone's guess at this point as to how long the precip remains
frozen and how much accumulation we receive. I would not rule out an extended period of
ice or snow. I also would not rule out the chance that all of this turns over to plain rain
tomorrow. There are alot of questions which still need to be answered regarding this
upcoming weather event, so my suggestion is to check back tonight as I will update this
page around midnight or so, after all of the new model data is in. Obviously by that point
we would be into a nowcast, but this is a very volatile situation which could turn either way
(snowy and cold or a chilly rain). Again, my thinking is that by rush hour this evening, we
will see some precip moving into our region. The rush shouldn't be affected much, except
for some wet roads. Frozen precip should hold off until around midnight. It should change
to sleet first and then to a mix of sleet and wet snow, and finally to snow for a period in the
early morning. We could see accumulations close to an inch of snow/slush before any
changeover to freezing rain thereafter. There could also be a break in the precip tomorrow
around midday, allowing enough warmer air in at the surface to change all of the frozen
stuff over to plain rain. Just be sure to check beck tonight. For now, I suggest staying
tuned to the local weather reports on TV or radio until I have an update to add later
tonight. Take care.
