WKU Meteorology

As expected, in the past few hours, both WNKY and WBKO have joined the NWS in drastically lowering their temperatures for the Sat-Tues period. But interestingly, both WBKO and WNKY are downplaying the Thursday/Friday storm (both are predicting one inch for Bowling Green) even though they now think the storm will be mostly snow. Normally, you raise amounts when you downplay the likelihood of a mix or changeover to IP/Z/R.

In fact, there is some evidence that south-central KY could receive 4″ plus of snow from this storm. What is that evidence? Continue reading →

As I was writing the previous post, the NWS has drastically lowered their temperatures for the upcoming Sat-Tues period, in agreement with my discussion from yesterday. As of Monday afternoon, they had high temperatures in the low 30s with lows in the upper teens for Sat-Tues while I had highs from 20-24 and lows 8-12 (with talk of the possibility of sub-zero temperatures). WBKO also had highs in the lows 30s and lows in the upper teens while WNKY had highs in the upper 20s and lows in the mid teens with no talk of sub-zero temperatures. Continue reading →

Everything from Monday’s discussion is on track. The NWS is starting to get on board with just how bitterly cold it will be across the eastern CONUS this weekend. The Duluth, MN forecast office noted Tuesday morning that some parts of northern MN may experience lows of -45 degrees F in the Sat-Tues time period. That same air mass will be coming our way and the amount of modification (see prior post) will determine whether or not BGKY will dip below zero or simply have lows in the single digits.

There is an interesting battle going on between known biases in the computer models that could affect the accumulation from Thursday’s snowfall. Continue reading →

The last time Bowling Green, KY had a low temperature below zero (-2) was January 24, 2003. The week of January 21-27 averaged 14 degrees below normal and featured an average high/low of 28/11 (relative to normals of 43/25). The coldest day of that week featured a high of only 14 degrees, a full 30 degrees below normal! The overall synoptic pattern of a southward displaced polar vortex is very similar to what will occur over Super Bowl weekend. In fact, the synoptic pattern is also quite similar to the record breaking cold outbreak of January 18/19 1994, which saw temperatures fall to -11 in Bowling Green and an all-time state-record -37 in Shelbyville. So if the overall synoptic pattern is very similar to these bitterly cold extremes, then why am I not predicting sub-zero low temperatures for Bowling Green? Continue reading →

After an anomalously warm start to the winter for the mid-south, seasonable temperatures (30s/40s) have returned since 1/16. So why have we remained snowless? The primary reason for that has been the pattern in the upper levels of the atmosphere. Since the El Nino sharply weakened mid-month, the overall synoptic pattern across the U.S. has yielded a sharp ridge over the western U.S. with a broad u-shaped trough over the east. This pattern does two things…1) Cold air masses from the arctic easily move southeastward across the U.S. every few days resulting in a temperature pattern of cold, warmer, warmer, cold, warmer, warmer… and 2) any storm energy coming across the northern Rockies or from the sub-tropics is quickly pushed eastward by the fast-moving jet stream before a large storm can develop. The arctic air is able to push all the way into the Gulf of Mexico which prevents any warm, moist tropical air from getting involved with the storm. For a winter storm to intensify, a few things have to happen… Continue reading →