Wednesday, June 06, 2012

Early Next Week: Hot or Not?

Just a brief entry this evening to look at next week. Models have been fairly consistent at advertising a brief dose of hot weather heading into next week. The forecast high in our PM forecast shows 90+ on Monday. But the question is....will it definitely happen? The answer is maybe...but not if you believe the latest GFS model. Take a look at the two images below from the PSU EWall...

This morning's European model forecast for Monday

This morning's GFS model forecast for Monday

The top panel shows the European model's forecast for Monday morning. The bottom one is the GFS. The top left panel in each of those images is the 500 mb pattern, or what's happening at about 20,000 feet up. Both show a rather large ridge aloft, which would be conducive to very warm temperatures. 

But the top right-hand panel on both of the images shows the surface solution. On the European, high pressure builds into the region, along with a weak quasi-Bermuda high type setup offshore. This allows southerly and westerly winds, which would allow for warm temps and a good shot at 90+ on Monday. However on the GFS model, you've got a weak low sitting just offshore, along with high pressure in the Canadian Maritimes. This allows for a broad and large scale onshore flow pattern to take shape, which would drive temperatures back considerably off the forecast...keeping interior areas (Rochester, Syracuse, Buffalo, Pittsburgh, etc.) warm, while knocking Philly through Boston back, with highs possibly only in the 70s or low 80s. The GFS is notorious for gaffes in certain situations such as this, but the trends are there (and we're close enough in) to at least classify this as a forecast risk. It will be something worth watching over the next couple of days for sure, and you'll be up to date on the latest right here.