October: Warm & Dry To End The Month

[Ptarmigan]

Could see some storms tonight ahead of the cold front.

[sleetstorm]

A line of thunderstorms have already formed over Northwest Montgomery County this hour.

[srainhoutx]

The Pacific front has moved through offering a couple of days of cooler/dryer weather before a return flow off the Gulf becomes re established. The next in a series of potent fall storms will enter the picture next week bring a rather widespread severe outbreak potential to the Southern/Central Plains along with yet another cold front sweeping S into the Lone Star State.

Also the tropics are looking to become active as a monsoonal trough begins to lift N and one if not two tropical disturbances develop in the Caribbean. While the Western Gulf is safe from any tropical mischief, there are indications that the SE Gulf and Florida/Bahamas may have an issue as a favorable MJO pulse and Kelvin Wave provide for an up tick in activity. Late October tends to favor that area as well as along the SE US Coast for tropical troubles.

Looking longer range, there are still indications that a much more potent Blue Norther type front is on the horizon near the end of October/early November as some mighty chilly air builds in our source regions and snowfall increases across Siberia and Western Canada and a very strong Arctic high pressure develops and begins to drop S into Canada bringing the coldest air of the season into the lower 48 as well as wintry weather well S into the Plains. We will see.

[jeff]

UM...Houston is along the Gulf coast nearly in the tropical latitudes...90's in October and 80's in November and December is not that uncommon. Stout mid level ridging over the northern Gulf will keep it warm for the next several days along with fast zonal flow north of this ridging keeping any cold air bottled in Canada. There are some indications of colder weather toward the end of the month into November, but this "cold" was expected last to arrive early next week and we all see that is not going to verify...so I have my doubts on such dramatic cold especially with models showing such extreme high pressures (1050mb+) over NW Canada.

[ticka1]

beautiful day out today! get out and enjoy it!

[srainhoutx]

I had a low of 49 in NW Harris County this morning. We should have a very typical October Chamber of Commerce weekend and for those lucky enough to be away from the city lights, the Orionid shower peaks before dawn on October 21.

Looking ahead, there continues to be indications of a late October active period with a landfalling EPAC tropical cyclone and a deepening Western trough and a rather stout cold front entering the picture as we close out October and begin November. We will see.

[wxman57]

Overnight model runs are much stronger with the front late next Friday or Saturday morning. Here's a meteogram I plotted. Rapidly-falling temps early Saturday morning and through the day on Saturday.

[JackCruz]

So I guess any type of El Nino is out of the question? I've been reading various blogs and forecast, models etc. And things aren't looking up. The only person that is optimistic at this point is Joe Bastardi lol...hopefully he's right. He seems to have a lot of faith in the JMA and the Brazilian model. I'll be okay with an average winter once we get some snow this winter and at least ONE week of very very cold temps!

[wxman57]

JB's not saying El Nino, just that the JMA model says a bit below normal for SE TX. As for next Friday evening's front, 12z GFS still says quite cool next weekend.

[srainhoutx]

It appears the Euro has flipped back and is in agreement with the GFS although about 6-8 hours slower with the cold front. This does appear to be the coldest air of the season so far and unless something changes over the next several days, a cold and dreary Saturday may be ahead for next weekend. We will see.

[srainhoutx]

The overnight guidance has come into much better agreement regarding the strong Arctic front expected to sweep S out of Canada during the coming week bringing an end to the warm weather as well as delivering a long awaited pattern change that has dominated the Lower 48 over the past couple of weeks. The zonal flow of late will switch to that of a very deep trough that will usher in some very chilly air that has been building in Siberia and Canada and bring that air S into the Plains and Texas.

There are indications that the coldest air of the season will dive well S into Mexico and even as far S as Cuba with this Fall cold spell. Locally, the trend has been to lower the temps daily with each cycle of guidance and there may well be a chance of near freezing temps in the Hill Country with this front. Over running conditions appear likely after the front passes as the sub tropic jet from the EPAC enters the picture. Upglide moisture over the top of the shallow cold air mass appears to be likely and will come as a bit of a shock after high in the lower 90's this week before the front arrives Friday into Saturday and sweeps S into the Gulf. Later in the week we'll fine tune the actual temps expected, but I wouldn't be surprised to see some 30's in the northern areas of SE Texas with strong blustery N to NW winds and a chilly rain next Saturday and possibly extending into Sunday. Stay Tuned! This may well be that long awaited Blue Norther that some have been hoping for.

[TexasBreeze]

I don't mind sunny and cool/cold, but clouds and rain with the cold for the birds.

[JackCruz]

Hopefully that 30 degree weather could make it down to the Cypress area...and bring some moisture with it jkkkkk

[texoz]

Interesting developments about cold potential. I'm guessing that potential for tropical development along East Coast that transforms into Nor'easter will have some input to this whole equation.

[srainhoutx]

Morning e-mail from Jeff:

Summer continues on this week under high pressure aloft and surface high pressure just to our east allowing a persistent onshore flow and a warm muggy air mass to continue in place. Fairly zonal flow aloft over the US will keep the above mentioned features in place through much of the week with the humid warmth continuing. SE TX lies along the eastern edge of a plume of deeper moisture moving northward from the western Gulf of Mexico which stretches NE into the Midwest ahead of short wave moving out of the southern Rockies. Thunderstorms will erupt across the plains today in this unseasonably warm pattern. Onshore flow pattern will keep

Upper air pattern is poised to undergo amplification by the middle to end of the week, while at the same time, a cold air mass builds and intensifies over NW Canada. By the middle to end of the week, the zonal (west to east) flow across the nation will be replaced by a more NW flow out of Canada as high pressure builds over the western US. This pattern will help dislodge some of the building cold air and send it southward down the plains by this weekend. The forecast models have been bouncing around with the idea of a strong cold front for days now, but have had significant timing and intensity differences between runs and models. Over the weekend the models have come into fairly decent agreement on the upper air pattern and the projected arrival of a cold front into the southern plains and TX Friday and Saturday. The main difference now is how cold does it get behind the front with the CMC showing a much colder air mass and the ECMWF and GFS showing a cool air mass, but nothing to the extreme of the CMC.

Given the amount of cold air build up over NW Canada this week along with a marginally favorable delivery pattern that supports a shallow cold front into TX, will go with a shallow cold air mass reaching TX on Friday and clearing the coast early Saturday morning. Strong cold air advection ensues post front with gusty NW winds and temperatures falling into the 50’s and 60’s. Post frontal shallow air mass looks to be overrun by WSW to SW flow above 900mb resulting in a thick cloud deck and periods of light rain on Saturday. Only slow clearing, if any, on Sunday as overrunning clouds hold. Would not be surprised is some locations remain in the 50’s all day Saturday, but this is about 10 degrees below current guidance numbers at this time. We have all week to tweak the temperatures for the weekend….as models get a better handle on how much cold air is going to dump southward, but the current very warm and humid conditions will be ended by this weekend!

99L:
A board area of low pressure has formed over the SW Caribbean Sea roughly 300 miles south of the island of Jamaica. Satellite images this morning show a well defined circulation in the cloud pattern with deep convective bands near and surrounding the center. It is highly likely that advisories will be initiated later this morning on a tropical depression.

The upper air pattern will result in a slow W to WSW motion for the next 48 hours followed by a turn toward the NNE to NE ahead of the deepening trough developing over the plains. There is fairly good guidance agreement on the system tracking over Jamaica and then across eastern Cuba and the central Bahamas by the end of the week. This should keep the system east of FL, however many models are showing a large circulation and the pressure gradient between strong high pressure over the mid Atlantic and the deepening tropical system will bring strong ENE winds, large waves, and possible squalls to the E FL coast.

Conditions are favorable for development, but the large sprawling nature of the circulation usually indicates a slow developing tropical system. Most model guidance keeps the system as a moderate to strong tropical storm with a few models bringing it to hurricane intensity. Think the best chance for development will be in the short term as the system lingers south of Jamaica over very warm waters and favorable upper air conditions. Tropical systems in this area in October can develop very quickly once an inner core is established. As the system begins to lift NE, increasing wind shear will begin to weaken the circulation due to approaching trough over the Gulf of Mexico by this weekend.

[txflagwaver]

OK so this weekend is Halloween decorating weekend...cold is good...rain and wind not so much. What are the thoughts on wet and windy between this weekend and Wednesday?

[jcarr]

Got to be chilly for scaring kids!

[srainhoutx]

The cold front is still on track and may arrive a bit earlier than previously thought. The GFS has sped up the arrival to early Friday morning while the Euro suggests a Friday evening passage. The is a potential for a low topped squall line with the cold front, although severe weather is not expect right now. Clouds with light post frontal rains may linger into Saturday with strong blustery winds from the N to NW. There still is some uncertainty just how 'cold' we will get, but it may not be out of the question that some northern areas struggle to get out of the upper 40's on Saturday. We'll see how that plays out in the next couple of days and fine tune things as we get a bit closer.

The bigger weather headline will likely be what happens along the East Coast early next week as a deep trough and cold air drop S and TS Sandy becomes entrained with the advancing cold front and a very robust upper low over the Great Lakes Region. Those with travel plans anywhere from the Appalachians on E into the Mid Atlantic to New England (North Carolina to Boston) and the I-95 Corridor may want to keep updated as there is some potential for a major EC Storm with a variety of weather that may well have major travel impacts for a very large area to the E. We will see.

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
959 AM EDT TUE OCT 23 2012

VALID 12Z SAT OCT 27 2012 - 12Z TUE OCT 30 2012


...POTENTIAL FOR MAJOR STORM OVER THE MID ATLANTIC & NORTHEAST
EARLY NEXT WEEK...

UPDATED THE PRELIMINARY FRONTS AND PRESSURES FOR DAYS 3 THROUGH 7
USING THE 00Z/23 EUROPEAN CENTRE ENSEMBLE MEAN, WITH A SMALL
INCORPORATION OF THE 00Z/23 EUROPEAN CENTRE DETERMINISTIC MODEL TO
LEND MORE DEFINITION TO THE SYNOPTIC GRADIENTS ACROSS THE NATION.
USED THE MOST RECENT FORECAST FROM THE NATIONAL HURRICANE CENTER
FOR THE TRACK OF TROPICAL STORM SANDY THROUGH DAY 5, WITH A CURVE
TO THE NORTHWEST DAYS 6 AND 7 BASED ON THE ECENS MEAN. THE 00Z/23
GEM GLOBAL CONTINUES TO CLUSTER WITH THE ECMWF FOR THE BEHAVIOR OF
SANDY ONCE IT TRANSITIONS TO A SUBTROPICAL SYSTEM, INDICATING THAT
THE CYCLONE GETS PULLED BACK TOWARD THE SHARP UPPER TROUGH CLOSING
OVER THE OHIO VALLEY. THE ECMWF AND GEM GLOBAL HAVE SEVERAL RUNS
OF CONTINUITY NOW WITH THE EVOLUTION OF THIS EVENT, WITH THE
DETERMINISTIC GFS LESS STABLE. THERE HAVE BEEN GFS ENSEMBLE
MEMBERS QUITE SIMILAR TO THE ECMWF/GEM CAMP FOR THE LAST FEW DAYS
OF MODEL CYCLES, PUTTING THE DETERMINISTIC GFS SOLUTIONS IN A
BROADER FRAMEWORK WITH THEIR TRACK OF SANDY WELL OVER THE OPEN
ATLANTIC. WILL BE UPDATING THE TRACK OF SANDY THROUGH DAY 5 FOR
THE FINAL PACKAGE WITH THE ADVENT OF THE NEW NATIONAL HURRICANE
CENTER FORECAST, AND ITS BEHAVIOR AS A SUBTROPICAL LOW THEREAFTER
AS PER OUR HOTLINE COORDINATION.


CISCO

[Portastorm]

The Euro for several days now has shown colder temps at the 850mb level than the GFS. If the latter wins out, then most of the NWS forecasts I have seen for temps should verify. If not and the Euro wins, we're going to see some temp busts if they don't adjust those forecasted temps.

We're going to have zonal flow aloft with a shallow cold airmass. Hmmm ... let's hope that continues for the next few months!

[JackCruz]

The Euro for several days now has shown colder temps at the 850mb level than the GFS. If the latter wins out, then most of the NWS forecasts I have seen for temps should verify. If not and the Euro wins, we're going to see some temp busts if they don't adjust those forecasted temps.

We're going to have zonal flow aloft with a shallow cold airmass. Hmmm ... let's hope that continues for the next few months!

What does a zonal flow aloft with a shallow cold air mass mean for SE TX?