POLK

767021 · 41.598, -93.575

drawing…

The record

Everything the slot carries, as measured. Series arrays are drawn above and listed here in full.

Event typeevent_type	Lightning
NOAA NCEI event IDncei_event_id	767,021
Episode IDepisode_id	127,578
Begin UTCbegin_utc	2018-07-01T02:00:00+00:00
End UTCend_utc	2018-07-01T02:00:00+00:00
Statestate	IOWA
County/zone typecz_type	C
County/zone namecz_name	POLK
Latitudelat	41.598
Longitudelon	-93.575
End latitudeend_lat	41.598
End longitudeend_lon	-93.575
Deaths directdeaths_direct	0
Deaths indirectdeaths_indirect	0
Injuries directinjuries_direct	0
Injuries indirectinjuries_indirect	0
Damage propertydamage_property	10.00K
Damage cropsdamage_crops	0.00K
Weather forecast office sourcewfo_source	Broadcast Media
Episode narrativeepisode_narrative	A frontal boundary was draped across areas just west of Iowa during the morning hours of June 30th, and slowly moved eastward into the state throughout the day. By the afternoon, it had made its way into central portions of the state, draping itself in a southwest to northeast fashion. Ahead of the front, the convective environment was ripe, with MUCAPE values in excess of 4000 J/kg and effective shear in the 30 to 40 kt range, with best values near the front. While there was reason for concern with regards to severe weather, such has hail and damaging winds, there was also strong concern for an area of west-central, north central or central Iowa to receive heavy rainfall with the boundary placement, potential outflow boundary locations, low level jet initiation, and a very moist environment. There was expectation for storms to be slow moving or training initially along the frontal boundary with propagation vectors opposing mean flow.\|\|Initially storms fired up in the early afternoon across parts of northwest and north central Iowa in the very unstable environment, producing severe hail and wind damage. Fortunately, given their progressive nature, no water issues were seen with that round of convection. As the afternoon progressed, convection increased across northern areas, but remained quiet further south into central and southern Iowa. The initial northern convection pushed out an outflow boundary that made its way into the I-80 corridor, acting as another area for convective initiation. By the late evening, convection had fired up along the parent frontal boundary as well as portions of the aforementioned outflow boundary, producing marginally severe storms in most cases. By the time the low level jet kicked in, areas around Des Moines had already received a couple inches of rain, and now found the area in line for much more. Overall motion of storms was northeastward, but with nearly stationary frontal and outflow boundaries, backbuilding was induced by the low level jet, which resulted in copious amounts of heavy rainfall right on top of the Des Moines metro and surrounding areas. While some damaging wind was still ongoing, the primary concern was for heavy rainfall, flash flooding, and eventually a flash flood emergency. The Des Moines metro area took on widespread amounts of 6 or more inches, including a few reports of nearly 10 inches. The main impacts revolved around flash flooding and the flash flood emergency with sewer systems and local streams absolutely overwhelmed. Dozens of vehicles were flooded or stranded, with numerous water rescues performed. Many streams were out of their banks, and an individual was swept away and killed during the flash flooding. One home had flooding and a gas leak that lead to an explosion of the home. Luckily all occupants had already been evacuated. Two streams with NWS stream gauge observations, Four Mile Creek and Walnut Creek, set all-time crest records. Countless basements and businesses were flooded across the metro area and dozens of homes were completely flooded out on the southeast side where Four Mile Creek flooding was the worst. Two businesses had roof collapses from the heavy rain as well. The flash flooding and stream flooding continued into the overnight hours on July 1, so another entry is made in July 2018 for this event as well.
Event narrativeevent_narrative	A lightning strike caused a garage fire damaging a portion of the garage.
Yearyear	2,018

Provenance

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Storage: spine