very rough cut at finding airports in a list that have better than 1000/2 weather.

taf.py

#!/usr/bin/env python3


import urllib.request
import xml.etree.ElementTree as ET
from datetime import datetime,timedelta
from collections import namedtuple
import math

#NOTE:  TAKE THIS AS AN INPUT
targetTime = datetime.strptime("2019-09-04T15:01:00Z","%Y-%m-%dT%H:%M:%SZ")
minus_one_hour = targetTime - timedelta(hours=1)
plus_one_hour = targetTime + timedelta(hours=1)

# Read the airports file to retrieve list of airports and use as order for LEDs
with open("airports") as f:
    airports = f.readlines()
airports = [x.strip() for x in airports]

# Retrieve TAF from aviationweather.gov data server
# Details about parameters can be found here: https://www.aviationweather.gov/dataserver/example?datatype=metar
url = "https://www.aviationweather.gov/adds/dataserver_current/httpparam?dataSource=tafs&requestType=retrieve&format=xml&hoursBeforeNow=5&mostRecentForEachStation=true&stationString=" + ",".join(
    [item for item in airports if item != "NULL"])
print(url)

content = urllib.request.urlopen(url).read()
root = ET.fromstring(content)
conditionDict = {"": ""}

for taf in root.iter('TAF'):
    stationId = taf.find('station_id').text
    print(stationId)

    qualifies = True

    for forecast in taf.findall('forecast'):
        if forecast.find('fcst_time_from') is None:
            continue
        if forecast.find('fcst_time_to') is None:
            continue
        fcst_time_from = datetime.strptime(forecast.find('fcst_time_from').text,"%Y-%m-%dT%H:%M:%SZ")
        fcst_time_to = datetime.strptime(forecast.find('fcst_time_to').text,"%Y-%m-%dT%H:%M:%SZ")

        latest_start = max(fcst_time_from, minus_one_hour)
        earliest_end = min(fcst_time_to, plus_one_hour)
        if latest_start <= earliest_end:
            #get ceiling, assumes always listed in ascending order
            ceiling = math.inf
            vis = math.inf
            if forecast.findall('sky_condition') is not None:
                for sky_condition in reversed(forecast.findall('sky_condition')):
                    if sky_condition.get('sky_cover') in ['BKN','OVC']:
                        ceiling = int(sky_condition.get('cloud_base_ft_agl'))
                        #print(sky_condition.get('sky_cover'), sky_condition.get('cloud_base_ft_agl'))

            if ceiling < 1000:
                qualifies = False
                print("disqualified, ceiling", fcst_time_from,fcst_time_to)

            #get vis
            if forecast.find('visibility_statute_mi') is not None:
                visibility_statute_mi = float(forecast.find('visibility_statute_mi').text)

            if visibility_statute_mi < 2.0:
                qualifies = False
                print("disqualified, vis", fcst_time_from,fcst_time_to)
        conditionDict[stationId] = qualifies