Category Archives: Commentary

Inconsistent Weather Forecasts- Commentary

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I’ve been looking at the weather for years.  I can’t remember a previous period of time where the major models have been so inconsistent with forecasts.   The major models, while often showing some disagreement with various features, seem to be in less agreement over the past month or so.

More importantly, the models themselves seem to change with their own forecasts from day to day.  Two examples this week- based on the forecast from the weekend, Tuesday was expected to be mild, but it wasn’t until Monday that it became apparent that temps would be near 60.  Thursday was supposed to be much colder at the start, now  not so until later in the day. What looked like snow is now a rain forecast.

Basically, this season, you can’t count on the models for a specific scenario beyond 2, maybe 3 days in advance.

I’m not sure why this is the case.  I have been reading that temperatures in the Arctic circle are very mild this year, with the cold pools of air being further south, in Siberia for example.  Not the norm. I suspect this is throwing off the models quite a bit.

Either way, weather forecasting so far this cold season has been more of a challenge than usual.

Going Secure

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I wish I could always secure these forecasts….but I can’t.  However,  I have just updated this site to a secure server SSL/TLS  format.  (    You should see a lock on your browser address line.

Unfortunately, for the time being, I’ve had to temporarily eliminate the nice radar and satellite loop images that were displaying here because they were being lifted from which is still an insecure server.

I’ll work on getting those images back.

Starting January 2017, Google will begin flagging websites who are not secure with a red  warning on their Chrome browser address line.  Initially, these warnings will only be commerce sites, but later, it will extend to all sites.  Eventually, Google will block access to sites that are not using https protocol.

Supposedly, all government websites will be moved to https protocol by December 31st 2016.

Eventually, Google plans to demote web search results for sites that are not using https protocol.

Let it be noted

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Let it be noted that on March 7th, Adam Joseph and Cecily Tynan declared that winter is over and it won’t snow again this season. That’s a bold prediction, not supported by the current extended GFS model.

Philly Winter Weather Update- 6:30 PM

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There’s a reason the TV weather people are essentially saying it will snow tomorrow and accumulations will range anywhere from 1-6 inches.  (That’s quite a range when you think about it!)

But the inconvenient truth is that even in established storms, the models have trouble with the exact placement of moisture plumes, the convergence of winds and the dynamics of lift that leads to precipitation.  As an example, the ‘blizzard’ a few weeks ago was expected to have its heaviest snow south and west of the city.   But the heaviest snow turned out to be north and west.  That error occurred with an existing storm system that was moving and strengthening in time, a relatively ‘simpler’ situation.

In the situation tomorrow, we are dealing with something totally different.  Tomorrow,  the models are ‘smart enough’ to predict the dynamic development of a new storm off the coast, but that’s where the limits of current atmospherics modeling end.   The models have already been inconsistent with the exact placement of this development and they simply can’t do the exact math with moisture, precipitation etc. because the exact initial state of the atmosphere where it will develop can’t be measured right this moment.

Anyone that get’s the exact snow amounts correct tomorrow in any specific location will do it only by luck.  And that includes me.

The best we can do tomorrow is talk about what the models are saying.  It’s likely not going to accurate enough.    For instance, the GFS has already backed off of it’s high QPF, while the NAM now shows another low pressure system forming towards evening at the coast, and its QPF is now very high, over 0.68 inches water.  So 1-6  inches is a good guess of a range.  It could be less and it could be more.

Sometimes, the most accurate forecast is being honest about the fact that we just can’t know precisely this time around.