Category: Heavy Rain

A Lot Of Weather To Talk About…

Mother Nature seems determined to put us weather forecasters to hard work as we get set to head into the Christmas season and welcome in 2014.  We’re tracking a major flood situation that will unfold across central Indiana over the upcoming weekend, followed by a reload of the cold and potentially a storm with a more wintry component as we get closer to the New Year.

First things first and that’s the significant flood threat in the short-term period.  Without trying to go into scare tactic mode, current model data would result in a downright dangerous flooding event for many low lying and flood prone areas this weekend.  Rainfall numbers are extremely impressive with this event and with a deep tropical connection, widespread 3-4″ totals are certainly likely, including some localized higher amounts.  Note the latest European chart, courtesy of the model suite off Weatherbell Analytics.  Needless to say, the Gulf of Mexico is officially “open for business” and will help contribute to excessive rainfall totals and, as stated above, potentially a dangerous flooding event this weekend across central Indiana.

ecmwf_uvz850_noram_16

Latest numbers averaged off a variety of computer models would place just under 4″ of rainfall down by noon Sunday, most of which falls between Friday and Sunday morning.  We note (2) waves of enhanced rainfall intensity set to impact the region.  As of now we’re targeting Saturday afternoon and again late Saturday night/ Sunday morning for extremely heavy rain, shown below.

ecmwf_slp_precip_mc_14ecmwf_slp_precip_mc_17

We still have time to watch the data and monitor the track of the storm.  It’s possible the “heaviest of the heavy” axis of rain shifts somewhat in the days ahead,  but it’s also important to note that even a light to moderate rain event combined with a frozen ground and a solid snow pack still in place will lead to flooding problems here across central Indiana.  The question of whether or not we’ll deal with flooding here this weekend shouldn’t be asked, but instead the question that remains is just how severe will the flooding be?  Stay tuned and if you live or work in a flood prone area, we would recommend preparing now for flooding.

Now, as we look ahead and focus on the Christmas to New Years period our thoughts will shift from a flood threat in the near term to one that’s more wintry.  We’ll turn dramatically colder Sunday afternoon behind the big rain storm and that will set the stage for a colder-than-average run up to Christmas. In fact, latest raw numbers off some forecast model guidance has some frigid readings ahead next week (upper single digits not ruled out for lows).

The upcoming 10 days off the European forecast model charts show an interesting scenario with the coming thaw, but the key word is brief.  Note days 6-10 are back into a colder-than-normal regime.

tavg_anom_ecmwf_conus_1

Additionally, we think we’ll have to deal with another storm prior to the New Year period and with the colder air back in place, there’s the threat we could have to contend with a wintry side to the next storm.  The details with storm number two will have to wait until we finish dealing with the first storm and associated serious flood threat it’s presenting.

Permanent link to this article: https://indywx.com/2013/12/18/a-lot-of-weather-to-talk-about/

Significant Flood Situation Ahead…

Your latest 7-Day video forecast can be found in the video player to the right of this post.

We’ve known for over a week now that we’ll have to deal with a pre-Christmas storm. Latest guidance suggests our region undergoes a 3-4 day thaw with a decidedly warmer southwest flow ahead of this storm.  Additionally, with the more northern track of the surface low, we’re looking at nearly all of the precipitation associated with this storm falling as rain.  Combine our frozen ground with a significant early-season snow pack and multiple inches of rain ahead in the Thursday night through Sunday time period and the stage is set for a significant flood situation this weekend.

Here’s a look at what the latest forecast models show.  We’ve posted the GFS, Canadian, and European models below to display total rainfall between Thursday through Sunday.  The majority of this rain falls in two waves- Friday and again late Saturday into early Sunday.

gfs_total_precip_east_22cmc_precip_by10_east_1ecmwf_tprecip_indy_21

If the rainfall numbers are even half of what is projected above, we’re looking at a significant flood situation.  Needless to say, if your property is in a low-lying area, or one that is prone to flooding, I would begin to prepare now for major water rise in the days to come.

Much more later!

Permanent link to this article: https://indywx.com/2013/12/18/significant-flood-situation-ahead/

Major Storm Brewing This Weekend, But Details Are Murky…

During the late summer and early autumn months we were trying to look at the big picture and potential drivers in the overall weather pattern for the upcoming winter and openly admitted the challenges that were ahead.  Here we are now into the second half of December and a much colder and snowier-than-average month is a virtual lock at this point.  Furthermore, consider this has all taken place without the presence of a favorable NAO or PNA.  Sometimes you have to look for other drivers in a pattern- in this case, the EPO, as well as a growing early fall snow pack across the border to our north.  Additionally, we made mention of the likelihood of a southeast US ridge periodically making itself known through the winter of ’13-’14.  You can read all of our thoughts posted earlier this fall here, or by clicking the Thoughts On Winter ’13-’14 page above.

As we look ahead towards the upcoming wintry challenge, we’re confident of the overall pattern, but the sensible weather that’ll ensue is still up for great debate.  “Gut” tells me central Indiana will be looking at a rain to freezing rain scenario, but this is far from set in stone, and sometimes forecasters who go simply off their instinct can get burned.  The pattern is one that (once again) will feature a pressing arctic front against resistance from the southeast US ridge.  With this type of scenario, I would advise against looking at each and every individual operational model run, but instead invest time studying the ensembles- an average of several multiple model runs as opposed to just one operational model run.   I can guarantee a variety of wild solutions ahead in the days to come, based off the operational runs. (Heck, just the past 24 hours have been reason enough to have the dramamine on hand :-)).  That said, let’s take a look at the latest GFS and European ensembles, two models that we rely heavily on in the mid range weather pattern.

First, the GFS, valid Saturday through Monday.

f120f144f168

Now, here’s a look at the latest European ensembles (left), again valid Saturday-Monday.

Geopotential32at32500hPa_North32America_120Geopotential32at32500hPa_North32America_144 Geopotential32at32500hPa_North32America_168

So what do all of these cool maps tell us?  Simply put, that “wintry mischief” is brewing for the weekend.  That much we know, but the details have to be ironed out.  It’s likely heavy snow and a significant ice storm looms for some of the Mid West and Ohio Valley for the upcoming weekend.  Is that Indianapolis or Chicago?  Perhaps in between?  It’s too early to know.  Additionally, in the “warmer” sector, heavy rains are likely to combine with an impressive early season snow pack for some to lead to flooding concerns.

A couple of additional items to note. Many times at this stage in the game (still 5+ days out) with this type of pattern, forecast models really struggle with handling low level cold air.  Cold air is very dense and, in this type of set up, can easily drain much further east and south than forecast at this juncture.  Additionally, sometimes the modeling can put too much “umph” into the associated surface wave that moves along the arctic front resulting in a further north track than what may actually occur when the event draws closer.  Just something to keep an eye on as we draw closer…

Needless to say, it’ll be particularly important to keep a close eye on the developing weekend forecast as we move forward.  It’s likely folks in the Ohio Valley region have to deal with significant precipitation amounts in the Saturday-Monday time period, including rain, freezing rain, and snow.

Permanent link to this article: https://indywx.com/2013/12/16/major-storm-brewing-this-weekend-but-details-are-murky/

Heavy Rain And Severe Outbreak Sunday

We continue to analyze the latest data concerning our pending severe weather episode ahead Sunday.  Today’s information continues to point towards the threat of not only a damaging straight line wind event, but the potential of multiple tornadoes across the central Ohio Valley.  The tornado threat would most likely occur with any individual super cells that develop Sunday afternoon.  The damaging straight line wind event would then be associated with what’s likely to be a squall line associated with the cold frontal passage Sunday night.  Needless to say, Sunday will be busy weather day across not only the Hoosier state, but for many folks across the Mississippi River Valley into the Ohio Valley.  Additionally, widespread heavy rain is also a good bet.  Let’s look at some data:

First, let’s look at some rainfall numbers.  The ECMWF (European forecast model) and GEM (Canadian forecast model) are the most aggressive with rainfall totals approaching the 2″ mark for many areas of central Indiana between Sunday and Monday.  The GFS isn’t as bullish, forecast a little more than half an inch on it’s latest run.  Officially we’ll go with a blend of all three models and suggest widespread 1″ type rains across central Indiana during the Sunday-Monday period.

ecmwf_tprecip_indy_21cmc_total_precip_east_15gfs_total_precip_east_15

Before we go further, we also want to highlight that winds will be strong and gusty Sunday even well away from any thunderstorms.  Winds will likely gust to 40-50 MPH simply by the tightening pressure gradient as surface low pressure begins to “bomb out” (rapidly intensify) on it’s journey into the Great Lakes region.

The dynamics are somewhat scary with this event and, as stated above, suggest not only an enhanced straight line damaging wind event, but also the potential of multiple tornadoes associated with any super cells that get going Sunday afternoon, well ahead of the squall line.  Despite a cold, dry air mass in place currently, the aforementioned strong southerly winds will help transport dew points into the lower to middle 60s come Sunday afternoon.  This will only help add fuel to the fire for storm development.

ecmwf_dew2m_indy_14

Let’s take a look at the official Severe Weather Outlook for Sunday, courtesy of the Storm Prediction Center.  Some highlights from their most recent discussion:

SOME UNCERTAINTY LINGERS...BUT TRENDS IN THE MEDIUM RANGE FORECAST
   GUIDANCE ARE INCREASINGLY SUGGESTIVE OF THE DEVELOPMENT OF AN
   ENVIRONMENT SUPPORTIVE OF AN OUTBREAK OF SEVERE THUNDERSTORMS ACROSS
   PARTS OF THE MIDDLE MISSISSIPPI VALLEY EASTWARD THROUGH MUCH OF THE
   OHIO VALLEY ON SUNDAY.
A 90+ KT 500 MB JET STREAK NOSING THROUGH THE OHIO VALLEY...COUPLED
   WITH STRENGTHENING SOUTHERLY WARM SECTOR 850 MB FLOW...PERHAPS IN
   EXCESS OF 70 KTS ACROSS PARTS OF THE OHIO VALLEY INTO THE LOWER
   GREAT LAKES...WILL CONTRIBUTE TO VERY STRONG DEEP LAYER WIND FIELDS
   AND SHEAR.  IT ALSO APPEARS INCREASINGLY PROBABLE THAT THIS WILL
   COINCIDE WITH AN INFLUX OF SEASONABLY HIGH MOISTURE CONTENT AT LEAST
   AS FAR NORTH AND EAST AS THE LOWER OHIO VALLEY...CONTRIBUTING TO
   SUFFICIENT CAPE FOR VIGOROUS STORM DEVELOPMENT.  SUPERCELLS WITH A
   RISK FOR TORNADOES WILL BE POSSIBLE...PARTICULARLY IN EARLY STAGES
   OF CONVECTIVE DEVELOPMENT...PERHAPS AS EARLY AS MID DAY ACROSS PARTS
   OF THE MIDDLE MISSISSIPPI INTO LOWER OHIO VALLEY VALLEY
EVENTUALLY...THOUGH...ACTIVITY PROBABLY WILL EVOLVE INTO A SQUALL
   LINE WITH DAMAGING STRAIGHT-LINE WINDS BECOMING THE MOST PROMINENT
   SEVERE THREAT.

day48prob

Permanent link to this article: https://indywx.com/2013/11/14/heavy-rain-and-severe-outbreak-sunday/

Wednesday Forecast: Rainy Midweek

Updated 11.05.13 @ 3:43p

Zionsville, IN Clouds are hanging tough this afternoon and rain isn’t too far off. Rain will increase Wednesday, becoming widespread the second half of the day. MUCH colder air will then blow into the region Wednesday night and Thursday.

Status-weather-showers-scattered-iconWednesday: Rain likely (0.55); 34/ 58

Wednesday will feature another gloomy day with rain overspreading the region from west to east. Scattered showers will be present through the morning hours before giving way to steadier, heavier rainfall during the second half of the day. Latest data suggests the cold front is speeding up from the last forecast update and this should result in a FROPA (frontal passage) Wednesday night. It’ll also be a windy day, with southwest gusts of 25-30 MPH during the day, shifting to the northwest Wednesday night.  Colder air will pour into the state behind the front, setting up a chilly, blustery Wednesday night and Thursday.

Status-weather-clouds-iconThursday: Partly cloudy; 33/ 47

A blustery northwest wind will blow Thursday and combine with a partly cloudy sky and an unseasonable chill to create a rather cold day. Winds will gust upwards of 20 MPH from time to time.

 

Status-weather-clouds-iconFriday: Partly cloudy; 30/ 51

A hard freeze will greet us as we prepare to wrap up the work week. Widespread lows around 30 will be commonplace before partly cloudy skies help temperatures rise into the lower 50s Friday afternoon.

 

Status-weather-clouds-iconSaturday and Sunday: Partly cloudy; 40 Sat, 36 Sunday/ lower to middle 50s

High pressure will remain in control of our weather Saturday.  While a weak storm system will pass through the upper Great Lakes region, it’ll remain well north of our area. Southwest breezes could gust up to 20 MPH Saturday afternoon. Otherwise, we’re looking at some mid and high level cloudiness and middle 50s Saturday afternoon and lower 50s Sunday.

Status-weather-clouds-iconMonday: Partly cloudy; 38/ 50

Dry and slightly cooler than normal conditions will greet us as we kick off the new work week.

 

Status-weather-showers-day-iconTuesday: Scattered shower (0.10); 36/ 50

The early look at next week shows more questions than answers.  For now we forecast scattered showers as our next weather system approaches from the west, but we caution this is a low-confidence forecast.  Be sure to stay tuned as we update things moving forward.

 

Permanent link to this article: https://indywx.com/2013/11/05/wednesday-forecast-rainy-midweek/

Wet Pattern Continues

While the midday model data continues to flip flop on the temperature outcome next week, one thing seems rather likely and that’s the idea we remain in a pattern that will produce significant rainfall over the next 10 days.

Let’s take a look at the ECMWF, GFS, and GEM (Canadian) for precipitation amounts over the next 7-10 days.

gfs_tprecip_conus2_65cmc_precip_by10_conus_1ecmwf_precip_10_conus_41

Model data paints a wet picture of widespread 1.5″-2″+ type rainfall totals over the upcoming 7-10 day period.

Permanent link to this article: https://indywx.com/2013/11/05/wet-pattern-continues/

Monday Forecast: Tracking Another Storm

Updated 11.03.13 @ 3:30p

Zionsville, IN It’s been a beautiful fall weekend across central Indiana. Aside from a couple of quick-moving showers Saturday evening, the weather couldn’t have been more perfect!  While the work week will start off on a pleasant note, we’re tracking another storm and significant blast of chill later this week.

Status-weather-clouds-iconMonday: Partly to mostly cloudy; 38/ 58

The day should dawn with bright sunshine, however, we note the latest high resolution short-term model data suggesting mid and high level cloudiness will be on the increase through the afternoon hours.  It’ll be a dry day with seasonable temperatures.  Enjoy!

Status-weather-showers-day-iconTuesday: Mostly cloudy; nighttime light showers (0.10″); 44/ 61

We’ll be in between high pressure to our east and our next approaching storm system to our west. As a result, a return southerly flow of air will help begin to transport milder air northward, along with increasing moisture Tuesday evening. The daytime hours should remain rain-free, but we’ll introduce a couple of light showers into our forecast Tuesday night.

Status-weather-storm-night-iconWednesday: Showers and thunderstorms, especially at night (0.70″); 49/ 60

A significant cold front will approach the region Wednesday. Showers will be likely through the day, but we still believe the heavier rains and embedded thunder will hold off until Wednesday night (especially after dark).  While we’re still monitoring any threat of severe weather, the bigger threat at this time appears to be another round of heavy rain falling atop a waterlogged central Indiana.  Stay tuned as we continue to analyze the latest data and update things accordingly.

Status-weather-showers-day-iconThursday: AM showers and thunderstorms (0.40″);  38/ 55 (falling)

The cold front will blow through the region Thursday morning.  Showers and thunderstorms will end west to east during the morning followed by a sharp temperature decline through the day, coupled with strong northwesterly winds gusting upwards of 30 MPH.

Status-weather-clouds-iconFriday: Partly cloudy; 29/ 48

A much colder air mass will settle into central Indiana Thursday evening and result in a hard freeze Friday morning. After waking up to lows in the upper 20s, highs will reach the upper 40s with partly cloudy skies.

 

Status-weather-clouds-iconSaturday: Partly cloudy and breezy; 40/ 55

Our fast-moving weather pattern will remain next weekend.  We’re tracking another storm system that will blow through the Great Lakes region Saturday. Current thinking places the track of this low too far north to impact the region from a precipitation standpoint, but we’ll certainly note a strengthening southwesterly wind Saturday followed by another shot of cold air Saturday night/ Sunday.  Highs next Sunday will likely remain in the 40s…

 

Permanent link to this article: https://indywx.com/2013/11/03/monday-forecast-tracking-another-storm/

Saturday Forecast: Chilly Weekend; Eyeing Another Significant Storm…

Updated 11.01.13 @ 10:53p Zionsville, IN After a day filled with heavy rain and damaging winds, we closed the week out with chilly, but pleasant weather conditions.  We’ll enjoy a…

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Permanent link to this article: https://indywx.com/2013/11/01/saturday-forecast-chilly-weekend-eyeing-another-significant-storm/

Tuesday Forecast: Changes Brewing…

Updated 10.29.13 @ 9:37a

Zionsville, IN It’s another calm, cold, quiet start to the day, but changes are brewing. These changes include warmer, more muggy air by tonight and Wednesday, widespread rain and storms for mid week, and another temperature plunge for the weekend.

Status-weather-showers-day-iconTuesday: Mostly cloudy; scattered nighttime showers; 0.10″; 37/ 62

After a calm, cold start to the day, clouds will increase and showers will develop tonight. We currently note widespread rain and embedded thunder across MO, but this will weaken as it encounters our dry air mass tonight. Light rain will likely overspread the region from southwest to northeast as we move through the nighttime hours.

Status-weather-showers-day-iconWednesday: Scattered showers; 0.10″; 55/ 67

The big story on Wednesday won’t be the rain, but instead the briefly warmer surge of air out ahead of our cold front. In fact, most of Wednesday should remain rain-free. Latest high resolution short term model data points to showers and a rumble of thunder exiting stage right Wednesday morning and while we can’t rule out an additional shower or thundershower through the day, most of the time will be rain-free Wednesday. South winds will begin to increase during the afternoon, gusting over 20 MPH.

Status-weather-storm-night-iconHalloween: Showers and thunderstorms; 1.10″; 59/ 66

A strong cold front will plow into the state Thursday night. Out ahead of this boundary, abundant moisture will surge north into the area. We’re not looking at all day rains Thursday, but target the afternoon-nighttime hours when rain and thunderstorms will be the most widespread. Additionally, we continue to monitor the severe threat with this system. Widespread and significant severe thunderstorms will be likely across southern IN and points south to include the western TN Valley. That said, severe weather reports will likely extend north to include central Indiana, as well. As of now, the primary severe threat appears to be from a damaging straight line wind perspective across our neck of the woods. Heavy rainfall will also be common as widespread 1″+ rains are likely.  Needless to say, you’ll certainly want to keep those weather radios tuned in Thursday.

Status-weather-clouds-iconFriday: Partly cloudy and breezy; 45/ 59 

The cold front will be to our east Friday, allowing the sunshine to return. It’ll be a breezy day, but the true cold air advection will hold off until Saturday, so temperatures will be very near seasonal levels Friday with a gusty northwest breeze.

imagesSaturday: Mostly cloudy; PM scattered showers (wet snow flake mixed in); 0.05″; 37/ 47

Fresh cold air will pour into the state Saturday and be accompanied by some upper level energy to create the threat of afternoon scattered showers.  Precipitation may mix with a wet snow flake Saturday evening. We think the day shapes up as a cold, raw day that will certainly require that jackets and sweaters.

Status-weather-clouds-iconSunday: Partly cloudy; 32/ 55

We’ll wrap up the weekend with sunshine returning.  Temperatures will begin to moderate closer to where we should be for this time of year, after a cold and frosty start.

 

Status-weather-clouds-iconMonday: Partly cloudy; 37/ 63

As high pressure moves to our east, it’ll allow a warmer return flow out of the southwest to help take over the region for the start of another work week. We’ll monitor a storm system to our west, but forecast dry skies for now next Monday.

Permanent link to this article: https://indywx.com/2013/10/29/tuesday-forecast-changes-brewing/

Monday Forecast: Halloween Storm In The Works

Updated 10.28.13 @ 9:01a

Zionsville, IN We’re opening the work week with cold and frosty conditions, but changes are brewing that will provide significant rain, strong winds, and thunderstorms by Halloween.  The details are below!

Status-weather-clear-iconMonday: Mostly sunny; 29/ 59

We remain under the influence of high pressure today and this will supply the region with plenty of vitamin D before “cloudier, stormier” times await later this week.  After a frosty start to the day, temperatures will moderate very near the 60 degree mark!

 

Status-weather-showers-day-iconTuesday: Increasing clouds; Nighttime showers; 0.25″; 37/ 58

A warm front will lift through central Indiana Tuesday afternoon. As the warmer, more moist air runs over the top of the chilly, drier air at the surface clouds will develop and we think scattered showers and perhaps a rumble of thunder begin to roll into the state Tuesday evening/ night.

Status-weather-showers-day-iconWednesday: Scattered showers; 0.25″; 52/ 67

We’ll remain in an unsettled weather pattern for the middle of the week. While most of Wednesday looks dry as of now, we can’t rule out a scattered shower or thunderstorm. Wednesday will be a warmer and windy day as south winds blow ahead of our approaching cold front. In fact, temperatures will approach the 70 degree mark for many Wednesday.

Status-weather-storm-night-iconHalloween: Showers and thunderstorms; 1.25″; 55/ 65

Showers and thunderstorms will become widespread on your Halloween, particularly Thursday evening and night. Some stronger storms are possible with a severe report or two not out of the question.  As of now, our thinking is the more widespread severe threat will remain to our south, and include portions of southwestern Kentucky and western Tennessee. Just make a mental note if your travel plans take you south Thursday.

Status-weather-showers-day-iconFriday: Scattered showers; 0.20″; 43/ 59 (falling)

The cold front will push east of the state Friday morning and a cooler air mass will move in for the weekend. We’ll include the mention of left over light showers/ drizzle Friday, but the bigger story will be gusty northwest winds and falling temperatures.

imagesSaturday: Mostly cloudy; Scattered shower (wet snow flake?); 0.05; 36/ 47

A much colder, northwesterly flow will be in control Saturday. This will keep the region much cooler than normal. Some upper level energy will rotate southeast over the region and may be strong enough to generate some scattered showers (potentially mixed with a wet snow flake).

Status-weather-clear-iconSunday: Mostly sunny; 31/ 55

We’ll wrap up the weekend with sunshine returning and cool, crisp fall conditions in place!

Permanent link to this article: https://indywx.com/2013/10/28/monday-forecast-halloween-storm-in-the-works/

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