Just How Hot is it Going to Get?
Location: New York
Author:
Michael Schlacter
Date: Friday, June 22, 2007
- Mississippi-to-Atlantic northern quadrant of Nation now on pace for Top-5 hottest month of June (since WW2)....
- Services may flip tunes every model run, but we remain adamant for hot entire (mid-May to mid-September) Season...
While our National forecasts remain essentially the same for the entire mid-May to mid-September Season (see summary points below), there are some noticeable transformations that will take place as we shift from May/June 2007 to July/August 2007 climate:
* Hot, critical day spikes will start crossing the 100°F threshold more frequently in drought regions (West, Southeast)
* Locations near the Great Lakes and Atlantic shorelines will have less common/less significant water-breeze cooled days.
* CDD/GDD surpluses will also be contributed to by muggy/warm evenings across the Northeast Quadrant/Quarter of Nation.
* Evapo-transpiration rates will keep temperatures elevated after sundown for suburban and even rural areas.
* Elevated Dew Points (non-Drought regions), will make 1.0 CDD's the equivalent of 1.5 CDD's due to T.H.I. and dehumidification demand.
"Forecasting the Forecast"...........
* NWS Outlooks (both 6-10 Day and 8-14 Day) have indeed revised much warmer the past 2 Days for the Eastern-Half of the U.S., and expect even more aggressive warmth depictions today [especially for the Great Lakes/Ohio Valley/Mid-Atlantic/Northeast]
Remember, "blank areas" on Government Outlooks Maps are NOT a forecast of Normal Weather, but rather a Non-Forecast in their opinion (i.e. anything can happen). Also remember that warm and cool contours are NOT indications of more intense warmth and cool, but rather their increasing confidence that the outlook will be in the warm or cool direction.
* Latest CPC Long-Range Climate Outlooks released today went much warmer for Eastern-Third of Nation for JULY and JULY-SEPTEMBER time periods, and now more in line with our own Summer projections (released in March).
Tropics:
Gulf of Mexico water temperatures and the Loop Current are presently much warmer than normal, and with our atmospheric vorticity projections, we believe there are good odds of another classified Tropical system forming in the near-U.S. waters (GOM, NW Caribbean, Bahamas) before June concludes. Computer models have spun up "Tropical Disturbances" every few days since February (so you are probably aware if not immune to the hype that pervades such information sources), but we'll keep you posted on real concerns if and when then emerge.
In addition to our normal forecast discussions, outlooks and advisories which you receive, you may also want to visit our Tropical Weather Page, to keep up to speed with the status of the Atlantic Hurricane Season, and other useful reference info:
We recently completed a compendium of historical New York Coast Hurricanes which you might find of interest:
We're not going to cry wolf every time a Cumulus Cloud pops up over Cuba, but if a legitimate Tropical Disturbance looks like it has good odds of being classified, you will always hear from us first. If you do not hear from us, then it is nothing to talk about.
Severe Storms and Drought status:
Unstable atmospheric conditions continue to dominate Nation's heartland, and the result is an astounding 975 preliminary U.S. tornadoes in 2007 to-date, about double the average we're supposed to have at this juncture. In other cases the severe weather takes the form of concentrated downpours & flash-flooding events (as we have witnessed across the Western Gulf Coast and Southern Plains region. But this often does not translate into widespread saturating rainfall (or the ground can not absorb downpours that fast). As a consequence, Drought (and corresponding wild fire risk) continues to be an increasing area of concern for 3 main areas we have been monitoring: (1) California/Nevada/Arizona, (2) Wyoming/western Dakotas, and (3) Southeast/Florida Peninsula. Precise storm tracks, rainfall quantity, and intensifying/expanding drought areas will need to be analyzed on a weekly basis in May 2007, to determine how they will define or refine Summer weather outcomes.
We recommend you print out the 5 bullet-points (below) summarizing our original (released in March) Summer 2007 outlook (mid-May through mid-September), and post it on your wall or computer for consistency, assurance, and comfort. The past 3-4 weeks have fit this pattern perfectly as will the next 12+ weeks (despite repeated fears & rumors), and we'll continue to keep you abreast of any intra-Summer deviations along the way:
* Regions warming the most compared to 2006 (last) Summer: Mid-West and Mid-Atlantic/Northeast
* Regions cooling the most compared to 2006 (last) Summer: Coastal California and Texas/Plains States ˆ
* Notable weather reminiscent of 2005: Periodic cool waves for Northwest and Rockies ˆ
* Notable weather reminiscent of 2006: Drought-induced Heat-spikes for Southeast States ˆ
* Most undervalued, significant weather parameter for 2007 U.S. Summer: Humidity/Heat Index with consequences for de-humidification demand, muggy overnights, and mitigation of "sunset drop-off" ˆ
From previous discussions, re-included for pertinence:
EAST...
So what happened the past 10 days when computer models said not a single day would hit 90°F across the Northeast Quadrant/Quarter of the Nation? It not only hit 90°F, but did so frequently, widespread and intensely (because computer models can't handle surface flux processes well in such a regime). Half-way through June 2007, Chicago already has hit the 90's 4 times, Cincinnati 6 times (compared to zero times in June through this date in 2006), Pittsburgh twice, D.C. & Baltimore 4 times, and Detroit, & New York City all 3 times. Even when winds occasionally shift to bring in cooler ocean air across coastal stations, inland areas as still baking such as this week when suburban New Jersey still hit 90°F and the Hudson Valley reached the upper-80's a few times.
CENTRAL/WEST/SOUTH...
The Texas-to-North Dakota "Plains Corridor" remains under a rather subdued pattern in line with our original Summer outlooks (see below), as do the Pacific Coastal communities [Los Angeles Airport has gone 40 consecutive days (and counting) without a single above normal day!] But the rest of the Nation (majority of West and Southeast) has been joining in on the warmth parade as well, but more in the form of drought-induced spikes (Sacramento has hit 102°F & 101°F, Salt Lake City has hit 100°F, Denver has hit 97°F twice, Las Vegas has hit 108°F twice, Montgomery AL has broken 100°F 4 times and even coastal Mobile AL has hit 100°F).
Obviously June 2007 is sultry and setting June records, (but some people are waiting for the contiguous U.S. to turn into the planet Venus before they get excited about Summer warmth), so for them we remind of these appropriate early-Summer paradigms:
1.) Summer is not Winter. Besides the obvious, dominant Winter regimes can be a lot more persistent than Summer regimes. While 20, 25 or even 30 consecutive Below Normal Days in the heart of Winter are witnessed, a frontal passage here, a foggy day there, a downpour here, a sea-breeze there, all make 'interruptions' to the overall monthly & seasonal regime quite common in the Summer. Hence, even the hottest Summers in recorded history have numerous cool days and cool weeks thrown in, so don't miss the forest for the trees and always keep the NET outcomes we research in the back of your mind.
2.) Don't need Heat to be Hot. Another difference between Summer and Winter is that small anomalies can go a long way. Monthly Summer Standard deviations for most U.S. locations are around 1/3rd the Monthly Winter Standard Deviations. For example, in June 2005 (which happens to also be a good, recent analog to this year) New York City "only" had 4 days >90°F and ended up "only" 2.8°F above normal for the month (including 10 below normal days), but that was good enough to be 1.5 sigma above the mean and the "hottest" June in NYC since 1994!
3.) Models do great.....when the weather is boring. All those aforementioned 'interruptions' give computer models a hard time, so their output becomes fickle, and consequently the short-term forecasters who rely on them put out very changeable or 'all things are possible' type forecasts. Matters get even worse when extreme drought, soil moisture and sea surface temperature anomalies come into play, which often triggers records to be set well beyond the scope of the models of short-term forecasts.
4.) Beware of Meteorologists in Climate Scientist clothing. Short-term forecasters (of which 95% of them are) provide valuable insight into hourly load-forecasting, 3-Day forecasts, synoptic rainfall and severe weather development. However, when they cross the line into 1-3 week outlooks and monthly climate predictions things get noticeably (and often deliberately) fuzzy. Consequently, hemispheric parameters (such as El Niño and La Niña) are incorrectly attributed, surface fluxes are undervalued, and Tele-Connections are misunderstood. Please let us know if you'd ever like us to comment on, decipher, explain or debunk any climate research or predictions you may come across from other weather sources, conferences or the Internet.
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