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Some parts of Iowa saw up to 6 inches of rain Wednesday. But did it help drought conditions?

Some parts of Iowa saw up to 6 inches of rain Wednesday. But did it help drought conditions?
During the overnight hours of August 1st into the morning of August 2nd parts of central Iowa received very heavy rain. Mainly the southern and southwestern parts of the state from thunderstorms that that drained over southwestern Iowa. You can see the uh rainfall accumulation from the day yesterday. Anywhere from two to as much as six inches of rain fell within *** narrow swath from roughly council bluffs over toward Atlantic, Creston and La Mona and there were even locally higher amounts there with some isolated spots reporting over or two inches. So let's show you the setup here that resulted in that heavy rain. We'll start with *** radar loop beginning Tuesday night at 11 p.m. Showers and thunderstorms begun to form roughly after midnight and they became widespread with intense heavy rain and frequent lightning developing from just north of the Omaha area down toward Atlantic, Creston and Lamon. And those showers and storms continue to move over the same locations repeatedly well into the morning hours of Wednesday and rain continued to fall even into Wednesday afternoon as *** weak disturbance finally pushed off to the east, ultimately ending the rain chances across central Iowa. So why did we result in so much heavy rain within such *** narrow zone? Well, let's talk about the storm set up from this past Tuesday into early Wednesday. We had *** stationary front draped out just to our southwest over parts of north central Kansas to Missouri with an area of low pressure attached to that frontal boundary, moving atop that front was *** low level wind or what we call *** low level jet. And that low level jet was transporting deep moisture from the southern plains. And as that moisture over road over with that frontal boundary that allowed for lift and the increase of moisture just to the north of the front. One of the values that we as meteorologists used to quantify the amount of available moisture in the atmosphere is precipitate water, which is the amount of liquid precipitation that would result if all the water vapor in the column of the atmosphere were condensed over *** certain location. And so Tuesday night and into Wednesday morning, we have precipitate water value use in excess of two inches over parts of southwestern Iowa, Eastern Nebraska and north central Missouri, which is 200% of normal for this time of year. So we had *** lot of moisture. We had *** source of lift and we had that moisture being drawn north over the front. And so the source of lift was able to produce widespread very heavy rain. In addition to that, the steering winds in the upper levels of the atmosphere. And the midlevels also resulted in *** set up for locally heavy rain to train over the same locations repeatedly. The winds, the mean steering winds in the atmosphere were blowing parallel to the front which resulted in training thunderstorms. So as thunderstorms formed just to the north of the bay boundary, they would move from northwest to southeast and the storms would train over *** location repeatedly similar to how trains go over box cars go over *** train track. And since the winds were roughly parallel, that allowed the storms pretty much stay in the same locations until the storms essentially rain themselves out. And there was not enough instability. So was Tuesday night and into Wednesday morning's rain enough to help alleviate our drought conditions. Well, maybe for parts of the state that will definitely take *** big dent out of the drought. But for us here in Des Moines, still nowhere near what we needed to end the drought. We only had *** little over *** half an inch and then you go back several months here this year. Uh Every month since the month of March has had *** rainfall deficit. So we are still running well behind here the in the immediate Des Moines metro area. And then not only do we look at Des Moines, but as we look at the statewide precipitation map over the last 30 days, South and western portions of the state have been doing pretty well with rain seeing over 100% of normal but still over central southeast eastern and northern Iowa running anywhere from 20 to 50% of normal. So still not doing good here. Uh with regards to precipitation for the drought and then you can see where that stacks up with regards to our precipitation deficit. Uh to get things back on track. We need at least 2 to 2.5 inches of rain over the last 30 days to consider to have *** normal month. The latest drought monitor released as of Thursday morning still shows drought conditions remaining the same. This week's rainfall will be reflected into next week's drought monitor. As the drought monitor data gap ends on Tuesday morning but still *** lot of drought issues across the state and it's going to take more widespread consistent rain over *** long period of time to help alleviate the drought. Our meteorologist Trey Fulbright with this weather explained.
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Some parts of Iowa saw up to 6 inches of rain Wednesday. But did it help drought conditions?
During the overnight hours of Tuesday into Wednesday morning, parts of Iowa received heavy rain from thunderstorms.The heaviest rainfall fell in a narrow zone over western and southern portions of the state, roughly along a line from north of Council Bluffs, Atlantic, Creston, and Lamoni. Roughly 2 to 6 inches of rain were reported within this zone, prompting a few flash flood warnings.So, what caused such a narrow zone of heavy rain, and was it enough to end the drought in this part of the state?The setup that resulted in the heavy rain began late Tuesday night and lasted into the mid-morning hours of Wednesday. Our weather pattern consisted of a stalled-out frontal boundary with an attached area of low pressure draped from northern Kansas into northern Missouri. A wind that resides just above the Earth’s surface that helps facilitate the transport of heat and moisture called the low-level jet was moving atop the front. Moisture at the surface was already collecting in the vicinity of the front, but the air from the low-level jet moving over the front only added more moisture and induced rising motion in the atmosphere to form showers and storms.The environment in which these storms formed was exceptionally moist for this time of year which led to efficient rainfall production. Precipitable water, a measurement that meteorologists use to quantify the amount of moisture in the atmosphere, was in excess of 2 inches over southeastern Nebraska, southwest Iowa, and north-central Missouri, which is roughly 200% greater than normal for this time of year.Once the storms formed, they trained, or moved repeatedly over the same locations as the winds in the atmosphere were running parallel to the front. Think of training storms as boxcars on a train track that are oriented in a fixed direction, only able to move where the tracks are laid out. Training thunderstorms in an excessively moist environment led to very heavy rainfall amounts in southwest Iowa.Despite this event being beneficial for parts of southwest Iowa, only small drought improvements are expected over the next week.The healthiest way for substantial drought removal is consistent rainfall distributed over a large area for a long period of time. Heavy rain events like this can provide some temporary relief but are not a feasible long-term solution.The Des Moines metro area continues to suffer with six months of rainfall deficit, and much of north, east, southeast and northwest Iowa faces some form of a deficit over the last 30 days.

During the overnight hours of Tuesday into Wednesday morning, parts of Iowa received heavy rain from thunderstorms.

The heaviest rainfall fell in a narrow zone over western and southern portions of the state, roughly along a line from north of Council Bluffs, Atlantic, Creston, and Lamoni. Roughly 2 to 6 inches of rain were reported within this zone, prompting a few flash flood warnings.

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So, what caused such a narrow zone of heavy rain, and was it enough to end the drought in this part of the state?

The setup that resulted in the heavy rain began late Tuesday night and lasted into the mid-morning hours of Wednesday. Our weather pattern consisted of a stalled-out frontal boundary with an attached area of low pressure draped from northern Kansas into northern Missouri. A wind that resides just above the Earth’s surface that helps facilitate the transport of heat and moisture called the low-level jet was moving atop the front. Moisture at the surface was already collecting in the vicinity of the front, but the air from the low-level jet moving over the front only added more moisture and induced rising motion in the atmosphere to form showers and storms.

The environment in which these storms formed was exceptionally moist for this time of year which led to efficient rainfall production. Precipitable water, a measurement that meteorologists use to quantify the amount of moisture in the atmosphere, was in excess of 2 inches over southeastern Nebraska, southwest Iowa, and north-central Missouri, which is roughly 200% greater than normal for this time of year.

Once the storms formed, they trained, or moved repeatedly over the same locations as the winds in the atmosphere were running parallel to the front. Think of training storms as boxcars on a train track that are oriented in a fixed direction, only able to move where the tracks are laid out. Training thunderstorms in an excessively moist environment led to very heavy rainfall amounts in southwest Iowa.

Despite this event being beneficial for parts of southwest Iowa, only small drought improvements are expected over the next week.

The healthiest way for substantial drought removal is consistent rainfall distributed over a large area for a long period of time. Heavy rain events like this can provide some temporary relief but are not a feasible long-term solution.

The Des Moines metro area continues to suffer with six months of rainfall deficit, and much of north, east, southeast and northwest Iowa faces some form of a deficit over the last 30 days.