Wintery Weather To Close Out the Week?

Currently, we're feeling the shock of Old Man Winter once again as 18 mph NW winds cut to the bone bringing in the much dreaded colder air. Temperatures will continue to drop tonight into the upper 20's, but will feel colder with the persistent winds in the morning. We will see temperatures into the mid 40's tomorrow under mostly cloudy skies. Tomorrow night represents one of the two bugaboos for this forecast. A weak front will move through the area in the early evening hours, providing some surface lift. With the dry, cold air already in place, there will be hardly any moisture to work with. The issue is that the temperature will be hovering around freezing at the time of and after passage. Models are indicating close to a trace of light to moderate precipitation, but closer inspection will have to be made into tomorrow as far as how much and precipitation type.

GFS 03Z (9 pm) 2/1/13 6 hr accumulated precipitation (in.) Notice our area is projected for a trace (.01 in) of precipitation over a six hour span. Very light precipitation expected.

After the frontal passage, winds will be slackening, skies will be clearing, and temperatures will be plummeting into the mid to upper teens for Friday morning. The high temperature for Friday will struggle to get over 30 as skies remain clear and winds will be low. Friday night lows will dip into the mid 20's, but will hold steady and slightly warmer after midnight. Warming will continue into Saturday afternoon with highs in the low to mid 40's. Right now, models are depicting a frontal disturbance crossing the area in the afternoon, but have not come together for a definite time. Simulated radar returns are suggesting early morning precipitation, but most of the moisture inflow, although small, will be occurring into the afternoon. As of now, I am trending towards an afternoon passage, hence, afternoon precipitation. Most of the heavier precipitation is projected to stay just to our south and southwest. We will have to closely examine this feature closer to Saturday in hopes to nail down the magnitude of moisture inflow, timing, and strength of this front. Precipitation is a real possibility, and considering these factors will help to distinguish type and amounts. Saturday night will have temperatures dipping into the mid 20's while Sunday is looking nice with high's nearing 40 degrees.

Days at a glance:

Thursday: High: 40  Low: 27  Winds: 14-18 mph W switching to 11-14 mph NW around 9 pm  Precip: 70% chance with type to be determined

Friday: High: 28  Low 16  Winds: 8-12 mph NW switching to W near noon  Precip: 0%

Saturday: High: 41  Low: 25  Winds: 13-17 mph SW switching to 8-11 mph WNW into evening  Precip: 80% chance with type to determined

Sunday: High: 41  Low: 26  Winds: 11-14 mph WNW  Precip: 0%

Forecaster: Austin Boys

Strong Cold Front Wednesday Morning

As the title insinuates, this week is looking like a tale of two halves regarding temperature. The first half of the week will help to shake off the shivers that were gained from last week's cold spell as temperatures climb into the mid to upper 50's on Monday and mid to upper 60's for Tuesday and early Wednesday. Get out and enjoy the warm, but a mostly cloudy few days. Light rain showers may affect us Monday night into Tuesday morning due to a warm front to our north across central Illinois and Indiana. All in all, this substantial warming is preceding a rude awakening for Wednesday morning.

NAM 15Z (9 AM) 1/30/13 showing winds (kt), temperature (deg F), and mean sea level pressure (mb). Notice the wind change and stark temperature boundary over south-central Kentucky marking the cold frontal boundary.

A line of storms associated with a strong cold front will quickly push its way through our area around 9 am. Precipitation should be relatively brief, but intense with amounts for Bowling Green likely to be .75 to 1 inch in total. Along with heavy precipitation, damaging winds will be a key hazard associated with the strong temperature gradient as the front passes our area. After the frontal passage, expect the rain to stop after lunch with a quick cool down Wednesday night as temperatures drop back below freezing for Thursday morning. The rest of the week will stay on the cool side with a mid-week update to cover the details.

Days at a glance:

Monday: High: 58  Low: 43  Precip: 10% rain showers late night  Winds: S 12-17 mph

Tuesday: High: 68  Low: 53  Precip: 10% rain showers early morning  Winds: S 17-23 mph

Wednesday: High: 60  Low: 33 Precip: 100% chance of heavy rain around 9 am  Winds: S 23-29 mph then switching to WNW decreasing to 5-6 mph throughout the day

Forecaster: Austin Boys

Ice This Morning!

Update (12:57 am): Precipitation has come completely to an end across the area and temperatures are rising above freezing. As of 11:55 it was sitting right at the 32 at the Bowling Green-Warren County airport, meanwhile mesonet sites across the area range from 31-32. We are also seeing a good amount of sunlight penetrate the clouds.  All of these factors are suggesting that the melting process is taking place.  This of course was not before a good amount of ice this morning with 0.10-0.20 of ice accrection. This caused numerous wrecks across southern Kentucky, some of the worst of which have been on I-65 between Bowling Green and E-town; as of this time the interstate was still reportedly blocked.  Temperatures will not get too warm today however as we'll likely only reach a high around 35-36 by this afternoon.  Temperatures will fall back below freezing sometime after 6 pm and thus any residual moisture may freeze again this evening and overnight and thus caution should still be used through tomorrow morning.  Lows tonight will fall to around 23 and we'll rebound to a high tomorrow near 38 under partly to mostly sunny skies.  Below are a couple of my favorite pictures that I took while walking around the Western Kentucky campus.

Ice can be seen on Normal Drive in Bowling Green.

A glaze of ice can be seen on this car parked at WKU.

A glaze of ice can be seen in the trees on campus. You can see that we picked up  between 0.1-0.2 inches of ice.

Update (8:27 am): Freezing rain is coming to an end across the county and across much of south-central Kentucky. Generally around a tenth to 2 tenths of an inch of ice has accumulated.  Roads are slick! As already stated there have been numerous accidents this morning so staying off the roads until midday when the temperatures are warmer is advised.  Just because this precipitation is ending does not mean that the roads aren't still slick.  Until temperatures rise above freezing, which is expected between 10-12 am, icy patches will be found on roads, sidewalks, etc...  The temperature is expected to rise to around 36 degrees today.

Update: An Ice Storm Warning has been issued for Warren Co and the surrounding counties until 1 pm CST. Details: http://forecast.weather.gov/showsigwx.php?warnzone=KYZ071&warncounty=KYC227&firewxzone=KYZ071&local_place1=&product1=Ice+Storm+Warning

I just wanted to do a quick update this morning.  As most know freezing rain is occurring across most of south-central KY including here in Warren Co just as we expected.  Temperatures have been holding steady in the upper 20s.  Numerous accidents have been reported including on I-65 and the Western Kentucky Parkway... roads are slick! This freezing rain is still expected to continue through around 9 am before precipitation will tapper off from west to east. Several bursts of freezing rain will move through between now and then however.  Most of the county will see 0.10-0.20 inches of ice by then.  Temperatures are still expected to warm above by noon so any lingering precipitation will not freeze and any accumulated ice can melt. If you must travel, use extreme caution.

Forecaster: Ryan Difani

Winter Storm Update

Currently an upper level trough is located over Manitoba with a jet max stretching from Minnesota down to northern Indiana and southwestern Michigan.  An upper level ridge axis stretches from Mexico up into Canada.  A vorticity maximum associated with the upper level trough.  Through time, the vorticity increases prolonging the life of the trough.  Moisture values associated with the trough are high with a narrow band of moisture influence coming from the Pacific ocean and wrapping around the ridge, then getting pulled into the trough.  This will help to set the stage for winter weather Thursday night into Friday morning.                                           

700mb Relative Humidity Map

The current temperature in Bowling Green is 38 with winds out of the west at 6 mph with partly cloudy skies. The temperature this evening will get down to 35, therefore be prepared if you have to go outside.  Surface low pressure is located over Canada at the North Dakota border, with the surface high pressure located over the Florida panhandle.  The low will move to the southeast tomorrow bringing cold air and the effects will be felt in the morning.  Tomorrow morning we will start out with a temperature of 31, and the temperature will drop throughout the day.  Winds will be out of the north causing the temperature to feel colder. 

The winter weather set up as it stands at this hour appears to be a freezing rain event, so keep the snow shovels packed away.  The precipitation could start out as sleet/snow then changing over to freezing rain.  The key to this set up is timing and the amount of moisture.  The timing of this event is varying with the models, however, late Thursday night into Friday morning during morning commute is highly likely.  The temperature Friday morning will be 31, which gives way to possible travel problems Friday morning.  We will continue to monitor this situation and will have the latest updates on this Winter Weather situation.

Forecaster:  Tyler Binkley

            

Gonna be a Cold One!

Currently there is a jet max over Canada stretching down to South Dakota which will propagate through the jet stream causing the trough, which is located over Manitoba, to dig.  A surface high pressure is located over the northeastern corner of Montana and northwestern North Dakota which will bring with it colder temperatures Tuesday and Tuesday night.  Relative humidity is 30% which indicates the dry air over the area indicating few clouds for tonight and tomorrow.  Winds are currently out of the northwest at 17 mph making the current temperature of 27 degrees Fahrenheit feel like 19.  For tomorrow, surface high pressure will be dominating the area, winds out of the northwest at 11 mph with a morning low of 15 with a wind chill at 8.  The high for tomorrow will be 26 with the wind chill making it feel like 10.  Be sure to grab your coat and mittens, but keep the snow shoes packed up for now.  The high pressure will move out of the area and by Thursday a low pressure system will move into the area bringing a wintry mix precipitation by Thursday night.  More on this later in the week. 

Wednesday:  High 43  Low 14

Thursday:  High 37  Low 23

Morning temperatures for Tuesday, January 22, 2013.

Forecaster:  Tyler Binkley

Winter Weather Recap and End of the Week Forecast

Recap of Last Night:
The forecast for last nights winter weather event was somewhat a challenge at times. A change in degree here or there really can mean the difference between an ice storm and rain. Last night, Bowling Green temperatures reached freezing later into the event. We saw some icing on elevated surfaces such as signs, hand rails, and car tops but nothing substantial. Areas as close as one county over in Butler County received more significant icing. The location of the freezing line (line of change over from rain to mixed wintry precipitation) was the saving grace for Warren County last night. This line stayed mostly off to our west which meant that most of our precipitation changed over to rain with only a short period of some freezing rain and sleet for parts of far western and northwestern Warren county.

Image taken from Tempestchasing.com. A great depiction of the location of last nights freezing line at 6 pm CST.


The most icing reported from downtown BG was only a thin coating on hand rails, car tops, and street signs. The trees and bushes in my area remained rain coated with no visible icing. While not as favorable for pictures sake, a huge near miss in the way of headache and danger.

Forecast Discussion for 1/17-1/20:

A strong upper level low located over Texas, Arkansas, Louisiana looks to advance northeast over Mississippi and Tennessee Valleys throughout the day Thursday. A surface low is forecast to begin development Thursday morning and become more organized over the border of Georgia and South Carolina by 18z (12 pm CST). This surface low will then advance northeast along the Carolinas. Far eastern Kentucky will remain on the cold side of this low (where colder air is the dominate advection). This will provide a chance for a light wintry mix event to occur in far southeastern Kentucky. 

09z ( 3 am CST) 1000-500 thickness MSLP and precipitation showing surface low development over GA/SC border.

Moisture looks to be sufficient for showers to develop as the low pressure system brings southeasterly winds and gulf moisture up along the cold frontal boundary extending from Florida to the Carolinas into the Atlantic.  HRRR High Resolution Rapid Refresh model shows a broad swath of precipitation from Mississippi to Northern Kentucky throughout the day Thursday. As the surface low develops, the heavier precipitation is shifted northeast as the low advances northeast.

24 hr forecast snow fall totals ending at 6 pm Thursday (CST). Shows far eastern KY in the 80% range for > 1 in with majority of eastern KY in the 30-75% chance of > 1 in.

Warren County could see a few light rain showers from this but no mixed precipitation is forecast though a few occasional flurries cannot be totally ruled out. Most wintry mix should stay to the east of Warren County. Any showers would be in the early morning clearing out later on in the day. Clouds should recede as well as the low pressure system passes to the east allowing some sunny skies to poke through after lunch time and into the afternoon as surface high pressure moves in behind. Partly sunny skies will be the trend into the weekend as we wait on our next significant weather system into early next week as another upper level trough becomes dug out from a jet max out of Canada. This system will bring the clouds and precipitation back into the Ohio Valley. Once under the influence of surface high pressure, temperatures will be slightly warmer into Friday and the weekend with highs in the mid to upper 40's even reaching the 50's by Saturday as our surface winds become more southwesterly.

NAM forecast surface temperatures for 18z (12 am) Saturday.

Forecast Overview:

Thursday 1/17: High, 43. Low, 24 . Northwesterly winds peaking between 5-10 knots. Slight chance of light morning showers. Clearing for some peak through sunshine into the afternoon with temperatures warming up. Mostly clear and cool night.

Friday 1/18: High, 43. Low, 26. Winds shifting to the southwest during the day. Mostly clear with few clouds. Winds peaking at 3-5 knots. 

Saturday 1/19: High, 50. Low, 32. Mostly clear and sunny and and overall beautiful day!

Sunday 1/20: High, 37. Low, 25. Clouds increasing into afternoon. Winds shifting more southerly. 

Cool Down to Continue Returning to More Seasonable Temperatures

Forecast Update: A Hazardous Weather Outlook for Warren County concerning possible mixed wintery precipitation event later into the evening. Visit NWS Hazardous Outlook for more information. Only small accumulations are expected but roads could become slick and motorists should be cautious of changing road conditions tonight!

 A Flood Warning remains in effect for Drakes Creek near Alvaton. Currently, the creek is at 16.6 feet with it's flood stage being 22 feet. The river is forecast to make it above this stage by Monday morning. The warning includes Butler and Warren Counties. For more information, visit NWS.

NAM current surface temperatures with cold front clearly depicted by strong temperature gradient extending from Maine back through Tennessee and Mississippi Valleys. 

Temperatures across Western Kentucky have taken a dive after the passage of a strong cold frontal boundary this evening. This boundary has also taken all the moisture with it leaving behind very dry cool air pooling in behind. Temperatures in Warren County have dropped around 25 degrees over the past 24 hours. Cold frontal boundary is expected to become stationary again over the Carolinas. Several wave impulses will rotate through at the 700 mb level and help kick off some post frontal showers over western Kentucky Sunday night into Monday drying out into Tuesday night. With temperatures very cold and freezing line nearby, we can expect some light flurries and mixed precipitation at times.

NAM and GFS models are in good agreement with placement of current trough axis over the western United States. The polar and subtropical jets are currently super-imposed upon each other helping to funnel the moisture for our weekend rain event into the Mississippi and Ohio Valleys. Models both show this trough staying semi-stationary and becoming more elongated and digging slightly to form a more organized upper level low. As this low develops it becomes slightly cut off and then becomes reabsorbed into the main flow during the day Wednesday. As the low develops, the subtropical jet again becomes independent of the polar jet as the low becomes absorbed into the polar jet. A zonal flow extends across the continental U.S. Thursday into Friday. This system looks to stay off to our west until the weekend when another cold frontal boundary will develop and push through the region. The rest of the week from Wednesday into Friday look to remain dry with more seasonal type temperatures.

Forecast Overview: 

Monday: High, 35 . Low, 24. Slight chance of morning showers clearing out with showers returning in the evening.

Tuesday: High, 40 . Low, 25. Slight chance of afternoon and evening showers with some mixed precipitation possible.

Wednesday: High, 45. Low, 30. Drying out with clearer conditions.

Forecaster: Emily Yates
Next Update: 1/16/13