Tuesday, August 20, 2013

An Early Bird Look Into Labor Day

Ten to twelve day forecasts aren't always known for their consistency (let alone 25 or 45 day outlooks) but one can glean some concept of sensible weather from a temperature standpoint this far out.  While we're still outside of a forecast range that I feel is relatively comfortable that generates specific numbers (82, 85, 88) for public consumption, patterns do provide a pretty good idea of warm or cool for a ten day forecast.  That would put us into the Labor Day weekend timeframe.

Modeling between the two better models out there -- the Euro and GFS -- show some consistency over two distinct features.  First, a ridge of high pressure over the Southern Plains and Midwest, with a warm regime generally extending across the middle of the country.  The longer range GFS keeps the high stronger in scope and intensity than the Euro, but both do generally show the ridge in the middle in the country.

The West Coast features a trough, with the East Coast on the fringes of the Plains ridge and in a general west-northwest flow (if you believe the GFS) or in a zonal flow (if you believe the Euro). This doesn't mean a cold Labor Day is in the offing -- it'll likely be pretty close to what's typical for late August and early September (lower/middle 80's for highs) but the odds of a variable weekend of weather may be a bit higher as we may be prone to cool fronts pushing through along the edge of the ridge as the trough regime itself is offshore (GFS) or relatively weak in Atlantic Canada (Euro).

What we can deduce from this is that Labor Day Weekend as modeled right now does not project to be a total washout, nor blowtorch hot throughout.  The GFS from last night suggests that Saturday will be the coolest (wake of cool front), Monday the warmest...but keep in mind it's the long range, less accurate part of the GFS so the specific details will probably change and may change a lot between now and ten plus days out.  However, the "big picture" is looking relatively consistent between the two models and as of now it does look like we won't be super hot, nor suffering through a miserable beach weekend.

Nor does there, at least as of now, look like there will be any immediate threat from the tropics in the Mid Atlantic. We're not sounding the all clear but it does look like we'll be ok from that standpoint. There might be stuff out there in the Atlantic but nothing looks like an immediate threat from this point.

The question eventually will turn to storm chances and specifically pinning down any thunder threats -- that part (and the highs for each day) will be fine tuned early next week...but given Labor Day is an important weekend for the Shore, the early bird look was warranted.