DAY 15, GIVE IT UP FOR DAY 15!!!!! The first measurable snow of the season for many cities along the Eastern seaboard is currently falling and it wouldn't quite be a snowstorm without the lack of common sense by your local television meteorologist. Yep, once again they fucked this one up but because they predict weather, they come up with some excuse as to why they severely under/over played their forecasts and keep their job for years to come. Due to these continuous fuck-ups by the local mets, I will be taking up the Chief Meteorologist position here at CBC and provide you with accurate, descriptive forecasts that will ensure your safety and proper preparation. Now since I do not have much background in places other than the Northeast for winter weather events, I will not touch on them but having lived in New York City most of my life and even a short stint in Boston and the nearby Philadelphia metro, I have been through some of the most intricate and tricky forecasts when it comes to winter weather and I even have some experience with hurricanes. Remember Sandy? I do. I also have 0 actual credentials in meteorology but over time you begin to understand it if you sit down and actually look at things and put the pieces together.
So let's begin with our first winter storm of the season: Winter Storm Avery as The Weather Channel dubs it. I had my eye on this one for a few days but never really got too excited about it's potential until yesterday. Models and local mets were consistent on the idea that the big cities would have a period of snow before changing all to rain in the early evening. They were right about the changeover the entire time but where they went wrong, AGAIN, was the timing of the changeover. Weather models such as the GFS and EURO are a guide and should never be a forecast. They can correctly predict storm placement and range of intensity but they flaw in thermal metrics. Since I focus mainly on NYC, that's where were going to start. At 2:00, the EURO and GFS were pretty confident in a temperature range of 35-37 degrees across the metro area with a wintry mix and eventual changeover around the 4:00 to 5:00 time frame. Outlets such as The Weather Channel, Accuweather, and WeatherBug took this model information and predicted just that with a trace-1" in and around the city with 3-5" in the NW suburbs due to an elongated period of snow since they can hang on to the sub-freezing temperatures for a bit longer. Well here's what they didn't look at. This storm actually dug a bit deeper in strength than modeled lowering the pressure change from -3 to -5 MB per 3 hours. In English, this storm has a bit more punch to it and a heavier precipitation rate inside the snow shield. The Low pressure that is in the Ohio Valley will eventually give way to a secondary surface Low off the coast of Virginia which will crawl NE while rapidly intensifying. Because the storm is stronger than anticipated, it is not absurd to say that the secondary Low will also be stronger and dig more. With this rapid intensification and more intense precipitation shield, the storm will undergo convective cooling. Basically, it will be snowing so hard that the system will create its own cold air and hold off the rain/snow line for a few more hours. This is a dynamic that the models cannot grasp onto and something that a credentialed veteran getting paid to do this should see. In Central Park right now, the temperature is 30 degrees and has been for quite a bit with the rain/snow line extending out 5 miles off the northern part of the Jersey coast. Originally predicted at this time: 38 and rain. Big difference. Having seen this over and over again, I said that a 3-5 inch snowfall for Philadelphia and NYC could definitely be in the field of play and what do you know; at around 10AM the weather outlets caved and upped totals to just that. Trust me, a 3-5 incher is nothing but that's quite a shift from a trace. Once again, I'm right and they're wrong. As for interior NY and PA, a widespread 10-15" snowfall will occur as that changeover will not happen. Boston will see a brief period of snow before the changeover where a quick 1-2" will accumulate. Not your storm Boston.
So for the rest of the winter, any snow event depending on the areas affected will be looked at in depth. Weather ain't hard. It's just about seeing patterns and understanding where those "trusty" models lie to us. Hope you learned something.
*All temperatures observed in Fahrenheit*
Take a note.
-Doorman
Kommentare