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> 0.6" RADAR
ESTIMATE OR 0.5" GAUGED IN FORECAST AREA |
|
Event |
Date |
Max
ALERT |
Max
CoCoRaHS |
QPE
STP |
ALERT
Alarms |
ALERT
Rain
Alarms |
Notes |
ADAM |
ARAP |
AURA |
BLDR |
BROM |
DENV |
DOUG |
JEFF
|
1 | | 0.47" | 0.57" | >1.00" |
|
|
HPO issued at 0900 with LOW Message
potential. M1’s
issued for Adams, Arapahoe, Aurora and DIA 1923 valid until 2100. A jet
to the N and S increased upper level support for fast-moving storms
that started at 1500-1600 and strengthened. The threat for
stronger storms in the E persisted until 2100. | X
|
| X
|
|
|
X
|
|
|
2 | | 0.75" | 1.05" | >1.50" |
|
| HPO
issued at 1038 with LOW Message
potential. M1’s
issued for the entire District at 2049 valid until 2359. A generally
quiet day until strong upper-level support moved into the area
enhancing the formation of hail-producing storms 1900-2000. Slow-moving
storms 2200-2400 produced mostly hail (2"-3"). Storms moved out of the
District by 0100.
| X
| X
|
X
|
| X
|
X
|
|
|
3 | | 0.24" | 0.19" | >0.50" |
|
| HPO
issued at 927 with MOD Message
potential. M1’s
issued for the entire District at 1143 valid until 2000. Initial storm
activity stayed south of the District. A second round of storms
produced heavy rainfall 1600-1900 and eventually poked into the
furthest northeast portions of the District before clearing out to the
east.
|
|
|
|
|
|
|
|
|
4 | | 2.58" | 3.74" | >3.00" |
| |
HPO
issued at 924 with MOD (plains) and LOW (foothills) Message
potential. M1 issued for the entire District at 1427 valid until
2100. A peculiar setup caused storms to anchor in place
throughout the day, resulting in the strongest storms between
1500-1800 and Flash Flood Warnings for Arapahoe, Adams and Douglas
Counties.
| X
| X
| X
|
|
| X
| X
| X
|
5 | | 0.71" | 0.68" | >0.50" |
| |
HPOs
issued at 921 and 2013 with MOD Message potential. M1s issued at
1535 valid until 2030 for the entire District and again 2121 valid
until 2359. Low temperatures helped suppress storms within the
District, although storms on the eastern plains restulted in late
eveing gust fronts that brought in a late round of storms west of the
District that fell apart as they entered the District.
|
|
|
| X
|
|
|
|
|
6 | | 0.47" | 1.09" | >0.75" |
|
| HPO issued at 0920 with HIGH Message potential. M1 was issued at
1102 for the entire District. While widespread moderate to heavy
showers were predicted, only one significant storm within the District
occurred around 1300, with gusty winds and hail up to 1.0".
Rainfall rates were limited by hail development, and also by storm
motions.
|
|
|
|
|
|
|
| X
|
7
| | 0.51" | 0.55" | >0.75" |
| |
HPO issued 926 with MOD Message potential for
the entire District. M1 was issued at 1407 valid until
2200. An active day produced at least one significant round of
storms that moved into the District between 1400-1500, with the
heaviest rainfall in northern Jefferson County/Broomfield.
|
|
|
| X
|
|
|
| X
|
8 | | 0.43" | 0.54" | >0.25" |
| |
HPO issued at 1001 with MOD Message potential
for the entire District. M1 was issued at 1324 valid until
2000. Initial storms moved onto, then off the foothills between
1500 and 1600, with a couple of storms producing brief heavy rainfall
around the Boulder/Jefferson line and further south into Douglas County.
|
|
|
|
|
|
| X
|
|
9 | | 0.51" | 0.55" | >0.50" |
| | HPO issued at 948 with MOD
Message potential for the entire District. M1 was issued at 1503
valid until 2100. A typical early summer day with just enough
fuel for storm development, initiating in the higher terrain by
midday. By 1700 a storm around Boulder produced the heaviest
rainfall of the day; 0.35-0.55" in 10-20 minutes.
|
|
|
| X
|
|
| X
|
|
10 | | 0.83" | 0.55" | >0.50" |
| | HPO issued at 922 with LOW
Message potential for the entire District. M1 was issued at 1808
effective until 2100. Multiple rounds of short-duration showers
impacted portions of the District but heavy rainfall stayed east.
|
|
|
|
|
|
|
| X |
11 | | 2.36" | 1.51" | >3.00" |
| | HPO was issued at 922 with MOD
Message potential for the entire District. M1 was issued at 1157
valid until 2200. Most activity stayed just beyond the District's
southern boundary but heavy rain including alarms were recorded in
Douglas County.
|
|
|
|
|
|
| X
|
|
12 | | 0.59" | 1.05" | >1.00" |
| | HPO was issued at 945 with LOW
Message potential for the entire District. M1 was issued at 1523
valid until 2200. An isolated storm in the northern Jefferson
County area developed quickly around 1400. Initially it contained
mostly hail, but moderate to brief heavy rainfall fell in Broomfield
and Adams Counties as the storm moved eastward.
| X
|
|
|
| X
|
|
| X
|
13 | | 0.39" | 0.74" | >0.75" |
| | HPO was issued at 1003 with
LOW & MOD Message Potential for the entire District. M1
issued at 1324 valid until 2200. Storm rapidly developed off the
foothills with moderate to brief heavy rainfall more widespread than
previous days. Low Impact Flooding for northern portions of the
District and into downtown Denver resulted from pulse-like storms with
gusty winds and cloud-to-ground lightning.
|
|
|
|
|
|
|
| X
|
14 | | 0.63" | 0.77" | >0.75" |
| | HPO was issued at 0955 with
MOD to HIGH Message Potential for the entire District. M1 issued
at 1220 valid until 2000. A pair of isolated storms propagated towards
the District; the northern dissipated over the District and the
southern one flowed along the higher elevations of the Foothills and
missed the District entirely. Only light rainfall was produced
within the District.
|
|
|
|
|
|
| X
| X
|
15 | | 0.47" | 0.24" | >0.25" |
| | HPO was issued at 0914with LOW Message Potential for the entire District. M1 issued
at 1535 valid until 2100. Storms initiated in the Boulder foothills at 1500 and weakened as they moved S into the District.
|
|
|
|
|
|
|
|
|
16 | | 1.22" | 2.03" | >2.00" |
| | HPO was issued at 1026 with
MOD
Message potential for the plains and High potential for the foothills.
M1 was issued at 1815
valid until 2300. High moisture levels were in place. A gust front from
a storm on the plains produced storms 1900-2000 moving N to S across
the District. Storms moved out at 2300.
| X
| X
| X
| X
| X
| X
| X
| X
|
17 | | 1.02" | 1.97" | >1.75" |
| | HPO was issued at 1017 with
HIGH
Message potential for the plains and foothills. M1 was issued at 1253
valid until 2200. Moisture levels remained high from the previous day's
rainfall. Storms formed SW of the District at 1300 causing training
storms until 1700 with lingering rainfall into the early evening.
| X
| X
| X
|
|
|
| X
| X
|
18 | | 0.94" | 0.90" | >1.00" |
|
| HPO was issued at 940 with
LOW
Message potential for the plains and MOD for the foothills. M1 was
issued at 1200
valid until 2200 for the entire District. Storms moved into the
District by 1200 producing moderate rainfall. An upper level
shortwave moved through the District 1500-1600. Storms formed
then moved E by 1700. Only weak storms continued into the early
evening.
|
|
|
|
|
|
| X
| X
|
19 | | 0.63" | 0.32" | >0.50" |
|
| HPO was issued at 926 with
LOW
Message potential for the plains and foothills. M1 was issued at 1341
valid until 2100. Moisture levels were high from the previous day.
Storms formed in the foothills at 1100-1200 producing brief heavy
rainfall but these storms dissipated as they entered the District. At
1700 storms to the N and S produced gust fronts over the District
producing cooling conditions. Rain ended by 1900. COMPLETE QPE DATA ARE
NOT AVAILABLE. |
|
|
|
|
|
|
| X
|
20
| | 0.94" | 1.46" | >1.25" |
|
| HPO was issued at 939
with MOD Message potential for the entire District. M1 was issued
1505 valid until 2200. Rapid storm development would occur over
multiple areas between 1630-1730 pm, with strong storms lasting through
2000-2100 producing raingall rates between 0.40-0.80" in 10-30 minutes
with isolated areas receivign between 1.00-1.50" of rain in and around
Douglas County.
| X
| X
| X
| X
|
| X
| X
| X
|
21
| | 0.63" | 0.82" | >0.75" |
|
| HPO was issued at 958
with MOD Message potential for the entire District. M1 was issued
at 1256 valud untill 2200. A more established round of storms
moved through in the later afternoon producing isolated moderate to
heavy rainfall from Boulder County through Broomfield County and
portions of northeastern Jefferson County to Adams County.
| X
|
|
|
|
|
|
|
|
22
| | 0.24" | 0.43" | >0.25" |
|
| HPO was issued at 954
with LOW Message potential for the plains and the foothills. M1
was issued at 1354 valid until 2200. Continental Divide storms
would weaken significantly as they moved off the higher elevations and
dissipate as they entered the District.
|
|
|
|
|
|
|
|
|
23
| | 0.55" | 0.77" | >1.00" |
|
| HPO was issued at 1002
with LOW Message potential for the entire District. M1 was issued
at 1626 valid until 2100. A cold front moved through the region
in the morning, increasing cloud
cover and producing showers in northwestern areas around Boulder.
Then
in the afternoon storm initiated along the foothils in the afternoon
and slowly moved eastward and into the District between 1630 and
1700.
Pockets of moderate to brief heavy rainfall moved through Jefferson,
Denver, Arapaho and Douglas Counties, with a Flash Flood Warning issued
for the Quarry Burn Scar. |
|
|
|
|
|
| X
| X
|
24
| | 1.26" | 1.98" | >2.00" |
| |
HPO was issued at 938 with
LOW Message potential for the entire District. M1 issued at at
1517 valid until 2300. Clouds clearing in the by midmorning would
result in better storm development in the southern portions of the
District, with pulse-like storms including storms over portions of
Douglas County producing over 0.50" in 10-15 minutes between 2000 and
2100 and storms moving into Jefferson County causing a Flash Flood
Warning for the Quarry Burn Scar. Storms persisted intot he
evening with a Flood Advisory issued aroudn the Franktown area for
persistent heavy rainfall from 2000 to 2200.
|
| X
|
|
|
|
| X
|
|
25
| | 0.63" | 1.32" | >1.00" |
| | HPO was
issued at 947 with HIGH Message potential for the entire
District. M1 issued at 1028 valid until 2100. Abundant
moisture led to a NWS Flood Watch. Slow moving storms enhanced
rainfall amounts, but storms struggled to form within the District
until 1530 when portions of Aurora and Arapahoe County received
0.50-1.00" Storm Total Precipitation. Some rainfall totals
in Douglas County added up over multiple rounds of storms.
|
| X
|
|
|
|
| X
|
|
26
| | 1.26" | 1.57" | >1.50" |
| | HPO was
issued at 952 with HIGH Message potential for the entire
District. M1 issued at 1205 valid until 2200. Abundant
moisture led to a NWS Flood Watch. Widespread storm development
with moderate to heavy rainfall occurred throughout most of the
District, especially in Douglast, Arapahoe and Boulder Counties.
The heaviest rain was just outside of the District.
|
|
|
| X
|
|
| X
| X
|
27
| | 0.24" | 0.38" | >0.50" |
| | HPO was
issued at 934 with MOD Message potential for the entire District.
M1 issued at 1540 valid until 2200. In spite of ingredients with
potential, storm development was capped by cooler temperatures which
limited convection and storm development.
|
|
|
|
|
|
|
|
|
28
| | 0.87" | 0.90" | >1.00" |
| | HPO was
issued at 1019 with HIGH Message potential for the entire
District.
M1 issued at 1235 valid until 2130. An uptick in moisture
resulted in efficient rainfall producing storms for the District with
severe storms out on the eastern plains. Storms in the District
produced brief heavy rainfall for portions of Jefferson and Boulder
County, with the latter having Low Impact Flooding rainfall just inside
the District.
|
|
|
| X
|
|
|
| X
|
29
| | 0.75" | 0.78" | >0.75" |
| | HPO was
issued at 924 with HIGH Message potential for the entire
District.
M1 issued at 1647 valid until 2220. Morning clouds limited
convection initiation until midafternoon, but by 1500 thunderstorms
with light to moderate rainfall potential developed across western
portions of the District, moving east. Surface winds transporting
a moist airmass into the District around 1700 fuled storm development
and rainfall potential, with an narrow area in Adams County impacted by
heavy rain.
| X
|
|
|
|
|
| X
|
|
30
| | 0.59" | 0.44" | >0.25" |
| | HPO was
issued at 941 with LOW Message potential for the entire
District.
M1 issued at 1355 valid until 1900. A day of borderline activity
left most of the District dry. A very weak upper-level
disturbance produced one strong cell in the Boulder area in the
afternoon, with moderate showers in Jeffersion, Broomfield and Adams
Counties. Stronger storms later in the afternoon rapidly
developed along the foothills (Boulder/Jefferson Counties), but mostly
rained themselves out as they moved onto the plains, resulting in a
gust front with winds up to 50 mph in the District, but modest rainfall.
|
|
|
|
|
|
|
| X
|
31
| | 2.05" | 1.52" | >1.75" |
| | HPO was
issued at 1002 with MOD Message potential for the entire
District.
M1 issued at 1456 valid until 2200 (extended to 0300 9/5).
Multiple rouns of storms impacted the District beginning at 1500.
The initial round brought moderate to heavy rainfall, up to 0.75," for
western portions of the District. A second round of storms formed
between 1700-1800 behind a gust front. Pulse-like showers
impacted areas along the Jefferson County foothills but rained
themselves out before moving into the District through midnight.
Another strong round of showers brought heavy rain of over an inch in
20-40 minutes for ares around Boulder between 2400 and 0100.
| X
| X
| X
| X
| X
|
| X
| X
|
|
|
|
Maximum 24-hour
value |
Maximum 24-hour
value |
Maximum
Radar
estimated
24-hour
precip |
Alarm Log |
Rainfall
Rate Alarm |
|
ADAM |
ARAP |
AURA |
BLDR |
BROM |
DENV |
DOUG |
JEFF |
