Weather Discussion: KSTL Dec 11 2009

For Friday: Temperatures will remain in the 20's until late morning when the skies clear and the wind shifts south-west bringing the high into the upper 30's by mid-afternoon. Blustery winds reaching 13 knots during the day will slow to 7 knots and shift south in the evening. There is a slight chance for freezing drizzle on Friday night, precipitation amounts will be trace.

KSTL Forecast for Thursday

Nothing too exiting for thursday:
Expect clear skies and cold conditions. As ridge moves
into the area temperatures will settle but will remain cold...
gusty conditions will make windchill a major factor.

Forecast Discussion For Wednesday @ 6Z till Thursday @ 6Z

The period will begin with the storm moving out of the area by 12z on Wednesday and the area beginning to dry out being on the back side of the trough and surface low. These features will usher in the coldest air yet for season with temps not warming any above Tuesday's lows. Wednesday night's lows will be plunging into the teens. With the tight pressure gradient associate with the low to the north east winds will be above 20kts for most of the period. With the low temperatures and high winds it's going to feel a lot colder than what the thermometer reads.

Thursday's KSTL Discussion

With the first major out break of Canadian cold air, this period is featured with cold air advection and surface high pressure. Both the GFS and NAM show 850mb temperatures getting as low as -10C with the flow from the west turning south west 00z Saturday. This will signify the trough axis passing of over the area. That will be the beginning of temperatures moderating for weekend.

KSTL Dec 3 2009

The cold front moves out of the forecast area Thursday but the cold temperatures linger due to mixed layer CAA following the front. Lingering flurries are possibe before 11:00am, cloud cover should diminish in the afternoon. High temperature will be in the upper 30's, low in the low 20's daytime cold NE winds around 12 knots dropping to 8 knots and shifting NW in the evening. Cold temperatures will remain through Friday.

Wednesday Forecast for KSTL

Two low pressure systems approaching the area will result in some rain throughout the day, changing to snow in the early evening. From most of the models, it looks like the worst weather will just miss the area, as the low associated with the shortwave trough tracking from the NW and the Texas Low racking to the NE converge east of KSTL. Most of the local precip will result from the descending cold front, with some wrap around from the second low. Temperatures will remain low through wednesday, and I am expecting it to be lower than what the models forecast. Winds will be gusty and high throughout the period.

Errors in the model forecast track for either low could result in significantly different weather either way, with more precip if the lows converge closer to KSTL, and little to no precip if they converge further east of the area.

Friday's Forecast for KCLE

Going into friday the low system continues to track slowly to the N-NE, with high pressure building behind it. Expect a slight chance of precip in the early hours, continually tapering off as the the day progresses. It will be mostly cloudly all day, and maximum temperatures should be lower than those for the past few days as a cold westerly flow advects into the area.

Thursday's KCLE Discussion

The period starts with a low over south eastern Missouri and as the period progresses the low moves north to almost NNW and late in the period turns east to move directly over KCLE. This will mean cooler temperatures and precipitation for the area. Both models agree on the track of the low, but differ on when the bulk of the precip will occur. The NAM as the majority falling Thursday morning while GFS is earlier and shows the precip dying down during this time. Either way the ground will be wet on Thursday with clearing ocurring with a turn to westerly flow Thursday evening. High temperatures will be a degree or two cooler with the cloud cover, but as the low moves east and the flow turns westerly cold air advection will kick.

Forecast discussion for Cleveland, Ohio; Wednesday Nov 18, 2009

The low pressure system presently lingering over lower Illinois and Indiana will drift into the Great Lakes area Wednesday into Thursday bringing light precipitation to the forecast area. Wednesday rainfall will only amount to about a tenth of an inch, this rate will increase on Thursday. High temperatures will remain in the mid 50's while lows will not drop below 40 degrees and winds will be steady around 14 knots. The moisture will last into Friday when a high pressure system should halt precipitation.

KCLE Week 2 Outlook

A big upper-level low over the middle of country will play a crucial role in KCLE WX pattern this week. This upper low will slowly make its way across over the the Great Lakes region by Wednesday/Thursday. This will bring temperatures back down towards normal values unlike what were observed last week. Partly cloudy to cloudy conditions will dominate the sky coverage for much of the week. The best chance of measurable precip will likely to occur when the system passes over the forecast area on late Wednesday night into Thursday morning. Light isentropic upglide (overrunning) precip will occur before the the system passage.



~Ng

Friday, November 13 KCLE weather discussion

Calm and pleasant weather conditions persist for Friday and Saturday. Friday, light fog is possible in the morning and should clear by noon so long as surface heating is not obstructed by cirrus cover. Expect highs around 60, lows in the upper 30's, light winds and a few degrees warmer on Saturday. Mild conditions last until Sunday when the high will drop to the lower 50's due to a low pressure system that could bring light precipitation.

Thursday Forecast for KCLE

Nothing exciting to report... 

Persistence forecast should hold ... conditions will be much like wednesday.  

High pressure system is dominating the region...expect cooler morning temperatures due to the clear skies and NE flow... will be breezy, so temperatures may feel cooler due to windchill

Expect clear skies and sunny conditions throughout the day... 

Thursday's KCLE Discussion

Persistence is the forecast for Thursday and Thursday night. With high pressure center over the region and a high amplitude ridge supporting it. This will cause sky's to be clear and winds to be calm. High temperatures will be a degree or two warmer than the pervious day with thicknesses rising, but lows will be able to plummet with the clear skies and calm winds.

Day 1 Outlook for Cleveland

A fast moving front cold front located over the IL/IN border will pass through KCLE right before the start of the day 1 forecast period. The part of the front that will make its way across northern OH will lack the necessary punch to create any significant precip. A high pressure will build in from the north after the FROPA and will dominate the weather for the rest of the forecast week. A mobile shortwave trough will create enough lift to create partly cloudy skies for the middle of the week. High temperatures are expected to be above seasonal while the lows will hover around the norms for the rest of the week.


For Day 2 - 4 discussion, please check back at noon each day.


~Dr. Ng

Three-year November Wind Climo Histogram

This histogram is created by Dr. Wagner.....maybe climo does have its advantage in forecasting.

Thanks, Dr. Wagner!



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Cleveland isn't so bad...is it?

Here is the 411 on KCLE:

Identifier KCLE
Normal High 51-47°F
Normal Low 37-34°F
Latitude 41.405683°N
Longitude -81.851915°W
Normal Wind Speed 9 knots
Normal Precipitation 0.11-0.12"
Elevation 245 m

KCLE is about 10km away from Lake Erie.


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In the end

Of all the things learned from this challenge it is that Stockton is really windy.

Friday's Discussion For Stockton

The period starts with a cut off low forming over the Baja and the upper level flow going from north west to west. There is a jet max approaching the northern California coast putting Stockton in the right the exit region. At the surface a cold front from a surface low in south eastern Alberta will approach the region with Stockton being on the very southern end of the front. Both NAM the GFS agree on the overall pattern and track of the front leaving Stockton in a questionable area of feeling any of the effects. Heights and thickness do fall so expect a cooler day and with the front staying north of the area not much of a pressure gradient to pick up winds. Low temperatures will be moderated by cloud cover with the associated system. With the placement of the jet and up level pattern, not expecting Stockton to see much of an effect from this system.

Day 7 Wx discussion

Strong upper level flow over the west coast today will bring cooler temperatures and higher winds tomorrow. Another indicator of impending cooler temperatures is the northwesterly flow and sky cover over the coast will that cause cool air advection over the forecast area. Fog is possible Thursday morning, lasting until the winds pick up mid day. Thursday temperatures will aproach 70 degrees, with lows around 50. Wind sustained around ten knots, will be gusty at times with mostly cloudy skies.

KSCK Weather Discussion for Wed Nov. 4th.

Conditions are going to be similar to today. Clear skies throught the morning, followed by upper level cloud ahead of the approaching cold front. As the ridge that has dominated the area moves easward, winds will shift to the SW, and continue to be light. Models predicting the High temperature to be less than tuesday.

Stockton Gala Days

Day 5 WX Discussion:

A board ridge remains off the western coast of the US. Winds will be remain light through our Day 5 forecasting period. Temperatures will stay above normal through this period.

~Doc Ng

The 411 on Stockton CA

Identifier KSCK
Normal High 74-68°F
Normal Low 48-45°F
Normal Wind Speed 7 knots
Normal Precipitation 0.04-0.05"
Latitude 37.889963°N
Longitude -121.226317°W
Elevation 8 m

Stockton is about 70 miles west of the Bay Area.


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KDEN 06Z 10/20 to 06Z 10/21

High tomorrow will be well below today, and temperatures will plummet even further after passage of cold front. The low temperature for this forecast period will in all likelihood occur at the end of the period as a result of cold air advection behind the front. This low temperature value could easily dip into the 30s by the end of the period. It would also not be surprising to see maximum winds just below or near gale force. It does appear that at least some precipitation will occur at the end of the forecast period, but the exact value is anybody's guess. The 12Z GFS forecasts relatively low precipitable water values for the end of the period, and I have decided to go on the low end with my precipitation estimate. However, if the 12Z NAM solution verifies, I could have egg on my face tomorrow night.

Tuesday Forecast Discussion

A weak Canadian cold front will move across the area within the next hour or so. Winds at GXY have backed already. The models seems to be in disagreements on high temp and precip as the NAM and GFS have the the leeside low forming in different location. Depending on your model of choice/trust, it could be either a soaker or a lighter rain event for the Denver metro area.

This past week, It seems like the GFS00/12Z runs have out performed the GFS06/18Z and NAM models. I am hesitant to give the edge to any models right now. On a bright note, most of the precip if it falls will be in the form of liquid.


~ Ng

Home Field Advantange Does Not Equate into a Win...Just Look at the Rockies.

Our new mission for the next two weeks is to forecast for Denver, CO. If you choose to accept your mission here is the 411 WRT Climo on the DEN site.

Identifier KDEN
Elevation 1656 m
Latitude 39.84°N
Longitude -104.65°W
Normal High 68-63°F
Normal Low 37-33°F
Normal Wind Speed 8 knots
Normal Precipitation 0.03"


WX Discussion:

Unsettling weather trend is installed for this week in Denver. A Denver Cyclone is forecast to develop in the middle of the week out to our southeast. This will increase our chances for cloudiness and precip for the next few days. It depends on where eventually the cyclone will set up, precip amount can be heavy for some places but mainly to our east. Temperature should be above freezing therefore, snow or freezing rain will not be an issue. Temperature will be close to normal. Overall, I don't think precip will affect KDEN as much as the NWS has it their discussion.

This weekend temperatures will bounce back to normal with a flat ridge building into the region. Next week, we could see another shot of cold temperatures as a Canadian cold front is forecast to pass through NECO.


~Doc Ng

Week Two CHS WX Dicussion

This week forecasts for KCHS should be more challenging as precipitation will play a role in our predictions. For the start of our day 5 forecast, lingering light precipitation will reside over the CWA. Temperatures will be unseasonable for Tuesday into Wednesday period. A shortwave will move north of the Carolinas by Wednesday night. This will usher in a chance of showery precipitation for Wednesday and seasonable temperatures and sunny skies by Thursday. On Friday, temperatures will be closer to normal and depending on how fast the next disturbance moves across the country, precipitation could be a factor towards the end of the day 8 forecast period.

Possible WX discussion revision during the midweek if warranted.

~ Doc Ng

Charleston Lows

From the looks of it tonight that high pressure is building into the Charleston area creating the warm air inversion aloft. If this holds true this should create a blocking of the upper level winds so that warm layer wont be able to mix out, this added to the clear skies over night will contribute to the radiational cooling overnight. Therefore, I believe the models are slightly high on the over night temperatures considering nearly no on or off shore winds at the surface contributing to radiational cooling and the subsidence of the high into the region. Then again I could be way off!

Suaave~

Let's do the Charleston!

We will be forecasting for Charleston for the next two weeks. Here are some useful information about the site

Identifier KCHS
Normal High 82-79°F
Normal Low 62-58°F
Latitude 32.89°N
Longitude -80.04°W
Normal Wind 7 knots
Elevation 15 m
Normal Precipitation 0.11-0.16"


Discussion:

A robust cold front with sweep across the SE US today. This front lacks the moisture punch to create any significant precip. Temperatures and winds will be the main concerns for this FROPA. Charleston CWA will be situated on the southern edge of the large upper-level trough so I do not foresee any significant change in the weather for the next 48 hrs. Temperatures and winds will be seasonal and precip chances are slim to none and slim just left town. Winds will be offshore for a good part of the week. Our next significant weather event will come this weekend as a disturbance moves across the Carolinas.

On a forecast side note, my experience with forecasting coastal locations W.R.T. winds has been quite challenging. My rule of thumb is to bump the forecast wind speed by at least a few knots since we are forecasting for max 2-min wind over a 24 hour period and not a hourly observation.

~Ng

New York, NY

KJFK's observations are taken at John F Kennedy International Airport as shown in the image below.




Since this is a coastal location, you may find sea temperatures to be useful.

Central Atlantic temperatures can be found here: http://www.nodc.noaa.gov/dsdt/cwtg/catl.html

Temperatures further north can be found here: http://www.nodc.noaa.gov/dsdt/cwtg/natl.html