Thursday, January 22, 2015

Thursday Morning Storm Update: Had to Make a Realistic Forecast

There it is guys the final map. As you all can see I made some adjustments.  Lets go through a few points here.

1. The storm will develop to be very strong with a low pressure center below 980.

2. Big problem is the sharp cutoff in moisture on the western side of this storm. The brown colors are dry air..

3. I have talked about no high to the north of the storm and now its really going to become a issue based on the latest model guidance which I can not ignore. Look at how much warm air surges into the mid levels of the atmosphere by 1 pm Sat below. This causes snow to change to sleet and plain rain in some areas. The problem is that is when a bulk of the precipitation will fall.

4. Areas where it should stay all snow are limited in how much precipitation or moisture falls out of the sky. This make there a small area where I expect 3-6 inches of snow.

5. What you are left with is a storm that is not going to be as significant as I expected. I think its very important to be honest and not try to slowly shuffle out of a bad initial forecast. I think you guys saw I always expected mixing and mentioned the warm air being an issue due to no high pressure to the north in my videos. However, I did not expect the warm air to dominate areas to the north west as much as its being shown. I also thought the storm would carry more moisture  on the western side thus having a longer period of snow. 

6. What you are left with is my initial area of 6+ of snow(the blue region on my old map) being reduced to 3-6 and that 3-6 being pushed to the north west. The mixing line was expanded further to the northwest as well. Maybe i'm being too hard on myself but I am not going to pretend that was the forecast from the start I def expected some higher amounts. At least I waited till today to have an accumulation map. 

I am a little disappointed I didn't have better foresight to weight some of these factors a little more. However the goal of this blog will always be to take a stance and that means a initial forecast has to be made before the day of a projected storm. Otherwise anyone can go to the National Weather Service web site and watch the forecasts change by the hour. So yes it means I will be wrong at times- hopefully I end up being right more than I am wrong.

Yes of course things can still change since we are still 48hrs away. I will keep everyone updated. Thanks for all the new followers and for checking in. Assuming things don't shift back to a snowier scenario in the next 48 hours hopefully I can do a little better with the initial forecast next time. 

We have another shot at snow early next week and I will start to focus on that as the days go on. 


  1. Yes, you're being too hard on yourself. I only wish all forecasters called it straight based on the data they have (instead of trying to keep to their original prediction). The data is the data and you have to use what you have, at the time.

    I'm betting that the higher elevations in NW Jersey that are at the edge of the "sleet/rain middle layer warmer air" thing get 6+" of snow. (I live in this area and have been wacked by past storms where it was alot of rain elsewhere but was all snow (and plenty of it) in the higher elevations. Thanks for the info Willy. Looking forward to your forecast for Monday's storm. All the best!

    1. Thank you for the nice words, and yes your right it's always possible. I remember a storm back in 2001 where it was mostly rain in most parts of the state and we got about 18" in NW NJ.. Let's see how next week pans out as well, I need to study the models after work today.

  2. Thanks for the effort you take in putting out these articles and videos.